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Reading to Learn Mathematics Reflections NAME ______________________________________________ DATE ____________ PERIOD _____ 9-1 9-1 © Glencoe/McGraw-Hill 483 Glencoe Geometry Lesson 9-1 Pre-Activity Where are reflections found in nature? Read the introduction to Lesson 9-1 at the top of page 463 in your textbook. Suppose you draw a line segment connecting a point at the peak of a mountain to its image in the lake. Where will the midpoint of this segment fall? Reading the Lesson 1. Draw the reflected image for each reflection described below. a. reflection of trapezoid ABCD in the line n b. reflection of RST in point P Label the image of ABCD as ABCD. Label the image of RST as RST. c. reflection of pentagon ABCDE in the origin Label the image of ABCDE as ABCDE. 2. Determine the image of the given point under the indicated reflection. a. (4, 6); reflection in the y-axis b. (3, 5); reflection in the x-axis c. (8, 2); reflection in the line y x d. (9, 3); reflection in the origin 3. Determine the number of lines of symmetry for each figure described below. Then determine whether the figure has point symmetry and indicate this by writing yes or no. a. a square b. an isosceles triangle (not equilateral) c. a regular hexagon d. an isosceles trapezoid e. a rectangle (not a square) f. the letter E Helping You Remember 4. A good way to remember a new geometric term is to relate the word or its parts to geometric terms you already know. Look up the origins of the two parts of the word isometry in your dictionary. Explain the meaning of each part and give a term you already know that shares the origin of that part. A B C D E A B C D E x y O R S T R S P T n A B C D A B C D

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Reading to Learn MathematicsReflections

NAME ______________________________________________ DATE ____________ PERIOD _____

9-19-1

© Glencoe/McGraw-Hill 483 Glencoe Geometry

Less

on

9-1

Pre-Activity Where are reflections found in nature?

Read the introduction to Lesson 9-1 at the top of page 463 in your textbook.

Suppose you draw a line segment connecting a point at the peak of a mountainto its image in the lake. Where will the midpoint of this segment fall?

Reading the Lesson1. Draw the reflected image for each reflection described below.

a. reflection of trapezoid ABCD in the line n b. reflection of �RST in point PLabel the image of ABCD as A�B�C�D�. Label the image of RST as R�S�T�.

c. reflection of pentagon ABCDE in the originLabel the image of ABCDE as A�B�C�D�E�.

2. Determine the image of the given point under the indicated reflection.a. (4, 6); reflection in the y-axisb. (�3, 5); reflection in the x-axisc. (�8, �2); reflection in the line y � xd. (9, �3); reflection in the origin

3. Determine the number of lines of symmetry for each figure described below. Thendetermine whether the figure has point symmetry and indicate this by writing yes or no.a. a square b. an isosceles triangle (not equilateral) c. a regular hexagon d. an isosceles trapezoid e. a rectangle (not a square) f. the letter E

Helping You Remember4. A good way to remember a new geometric term is to relate the word or its parts to

geometric terms you already know. Look up the origins of the two parts of the wordisometry in your dictionary. Explain the meaning of each part and give a term youalready know that shares the origin of that part.

A�B�

C� D�E�

AB

CDE

x

y

O

R�S�

T�

RS P

Tn

A�B�

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D�A

BCD

Reading to Learn MathematicsTranslations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-29-2

© Glencoe/McGraw-Hill 489 Glencoe Geometry

Less

on

9-2

Pre-Activity How are translations used in a marching band show?

Read the introduction to Lesson 9-2 at the top of page 470 in your textbook.

How do band directors get the marching band to maintain the shape of thefigure they originally formed?

Reading the Lesson1. Underline the correct word or phrase to form a true statement.

a. All reflections and translations are (opposites/isometries/equivalent).b. The preimage and image of a figure under a reflection in a line have

(the same orientation/opposite orientations).c. The preimage and image of a figure under a translation have

(the same orientation/opposite orientations).d. The result of successive reflections over two parallel lines is a

(reflection/rotation/translation).e. Collinearity (is/is not) preserved by translations.f. The translation (x, y) → (x � a, y � b) shifts every point a units

(horizontally/vertically) and y units (horizontally/vertically).

2. Find the image of each preimage under the indicated translation.a. (x, y); 5 units right and 3 units upb. (x, y); 2 units left and 4 units downc. (x, y); 1 unit left and 6 units upd. (x, y); 7 units righte. (4, �3); 3 units upf. (�5, 6); 3 units right and 2 units downg. (�7, 5); 7 units right and 5 units downh. (�9, �2); 12 units right and 6 units down

3. �RST has vertices R(�3, 3), S(0, �2), and T(2, 1). Graph �RSTand its image �R�S�T� under the translation (x, y) → (x � 3, y � 2).List the coordinates of the vertices of the image.

Helping You Remember4. A good way to remember a new mathematical term is to relate it to an everyday meaning

of the same word. How is the meaning of translation in geometry related to the idea oftranslation from one language to another?

R�

S�

T�

R

S

T

x

y

O

Reading to Learn MathematicsRotations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-39-3

© Glencoe/McGraw-Hill 495 Glencoe Geometry

Less

on

9-3

Pre-Activity How do some amusement rides illustrate rotations?

Read the introduction to Lesson 9-3 at the top of page 476 in your textbook.

What are two ways that each car rotates?

Reading the Lesson

1. List all of the following types of transformations that satisfy each description: reflection,translation, rotation.a. The transformation is an isometry.b. The transformation preserves the orientation of a figure.c. The transformation is the composite of successive reflections over two intersecting

lines.d. The transformation is the composite of successive reflections over two parallel

lines.e. A specific transformation is defined by a fixed point and a specified angle.f. A specific transformation is defined by a fixed point, a fixed line, or a fixed plane.

g. A specific transformation is defined by (x, y) → (x � a, x � b), for fixed values of a and b.

h. The transformation is also called a slide.i. The transformation is also called a flip.j. The transformation is also called a turn.

2. Determine the order and magnitude of the rotational symmetry for each figure.

a. b.

c. d.

Helping You Remember

3. What is an easy way to remember the order and magnitude of the rotational symmetryof a regular polygon?

© Glencoe/McGraw-Hill 492 Glencoe Geometry

Rotational Symmetry When the figure at the right is rotated about point P by 120° or 240°, the image looks like the preimage. The figure has rotational symmetry, which means it can be rotated less than 360° about a point and the preimage and image appear to be the same.

The figure has rotational symmetry of order 3 because there are 3 rotations less than 360° (0°, 120°, 240°) that produce an image that is the same as the original. The magnitude of the rotational symmetry for a figure is 360 degrees divided by the order. For the figure above,the rotational symmetry has magnitude 120 degrees.

Identify the order and magnitude of the rotational symmetry of the design at the right.

The design has rotational symmetry about the center point for rotations of 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°.

There are eight rotations less than 360 degrees, so the order of its rotational symmetry is 8. The quotient 360 � 8 is 45, so the magnitude of its rotational symmetry is 45 degrees.

Identify the order and magnitude of the rotational symmetry of each figure.

1. a square 2. a regular 40-gon

3. 4.

5. 6.

P

Study Guide and Intervention (continued)

Rotations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-39-3

ExercisesExercises

ExampleExample

Reading to Learn MathematicsTesselations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-49-4

© Glencoe/McGraw-Hill 501 Glencoe Geometry

Less

on

9-4

Pre-Activity How are tessellations used in art?

Read the introduction to Lesson 9-4 at the top of page 483 in your textbook.

• In the pattern shown in the picture in your textbook, how many smallequilateral triangles make up one regular hexagon?

• In this pattern, how many fish make up one equilateral triangle?

Reading the Lesson

1. Underline the correct word, phrase, or number to form a true statement.

a. A tessellation is a pattern that covers a plane with the same figure or set of figures sothat there are no (congruent angles/overlapping or empty spaces/right angles).

b. A tessellation that uses only one type of regular polygon is called a(uniform/regular/semi-regular) tessellation.

c. The sum of the measures of the angles at any vertex in any tessellation is(90/180/360).

d. A tessellation that contains the same arrangement of shapes and angles at everyvertex is called a (uniform/regular/semi-regular) tessellation.

e. In a regular tessellation made up of hexagons, there are (3/4/6) hexagons meeting ateach vertex, and the measure of each of the angles at any vertex is (60/90/120).

f. A uniform tessellation formed using two or more regular polygons is called a(rotational/regular/semi-regular) tessellation.

g. In a regular tessellation made up of triangles, there are (3/4/6) triangles meeting ateach vertex, and the measure of each of the angles at any vertex is (30/60/120).

h. If a regular tessellation is made up of quadrilaterals, all of the quadrilaterals must becongruent (rectangles/parallelograms/squares/trapezoids).

2. Write all of the following words that describe each tessellation: uniform, non-uniform,regular, semi-regular.

a. b.

Helping You Remember

3. Often the everyday meanings of a word can help you to remember its mathematicalmeaning. Look up uniform in your dictionary. How can its everyday meanings help youto remember the meaning of a uniform tessellation?

© Glencoe/McGraw-Hill 498 Glencoe Geometry

Tessellations with Specific Attributes A tessellation pattern can contain any typeof polygon. If the arrangement of shapes and angles at each vertex in the tessellation is thesame, the tessellation is uniform. A semi-regular tessellation is a uniform tessellationthat contains two or more regular polygons.

Determine whether a kite will tessellate the plane. If so, describe the tessellation as uniform, regular, semi-regular, or not uniform.A kite will tessellate the plane. At each vertex the sum of the measures is a � b � b � c, which is 360. The tessellation is uniform.

Determine whether a semi-regular tessellation can be created from each set offigures. If so, sketch the tessellation. Assume that each figure has a side length of1 unit.

1. rhombus, equilateral triangle, 2. square and equilateral triangleand octagon

Determine whether each polygon tessellates the plane. If so, describe thetessellation as uniform, not uniform, regular, or semi-regular.

3. rectangle 4. hexagon and square

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Study Guide and Intervention (continued)

Tessellations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-49-4

ExercisesExercises

ExampleExample

Reading to Learn MathematicsDilations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-59-5

© Glencoe/McGraw-Hill 507 Glencoe Geometry

Less

on

9-5

Pre-Activity How do you use dilations when you use a computer?

Read the introduction to Lesson 9-5 at the top of page 490 in your textbook.

In addition to the example given in your textbook, give two everydayexamples of scaling an object, one that makes the object larger and anotherthat makes it smaller.

Reading the Lesson1. Each of the values of r given below represents the scale factor for a dilation. In each

case, determine whether the dilation is an enlargement, a reduction, or a congruencetransformation.a. r � 3 b. r � 0.5c. r � �0.75 d. r � �1

e. r � �23� f. r � ��

32�

g. r � �1.01 h. r � 0.999

2. Determine whether each sentence is always, sometimes, or never true. If the sentence isnot always true, explain why.a. A dilation requires a center point and a scale factor.

b. A dilation changes the size of a figure.

c. A dilation changes the shape of a figure.

d. The image of a figure under a dilation lies on the opposite side of the center from thepreimage.

e. A similarity transformation is a congruence transformation.

f. The center of a dilation is its own image.

g. A dilation is an isometry.

h. The scale factor for a dilation is a positive number.

i. Dilations produce similar figures.

Helping You Remember3. A good way to remember something is to explain it to someone else. Suppose that your

classmate Lydia is having trouble understanding the relationship between similaritytransformations and congruence transformations. How can you explain this to her?

Skills PracticeDilations

NAME ______________________________________________ DATE ____________ PERIOD _____

9-59-5

© Glencoe/McGraw-Hill 505 Glencoe Geometry

Less

on

9-5

Draw the dilation image of each figure with center C and the given scale factor.

1. r � 2 2. r � �14�

Find the measure of the dilation image M���N��� or of the preimage M�N� using thegiven scale factor.

3. MN � 3, r � 3 4. M�N� � 7, r � 21

COORDINATE GEOMETRY Find the image of each polygon, given the vertices, aftera dilation centered at the origin with a scale factor of 2. Then graph a dilation centered at the origin with a scale factor of �

12�.

5. J(2, 4), K(4, 4), P(3, 2) 6. D(�2, 0), G(0, 2), F(2, �2)

Determine the scale factor for each dilation with center C. Determine whether thedilation is an enlargement, reduction, or congruence transformation. The dashedfigure is the dilation image.

7. 8.

CC

G�

F�

D�

G�

F �

D �x

y

O

J� K�

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P �x

y

O

CC

Reading to Learn MathematicsVectors

NAME ______________________________________________ DATE ____________ PERIOD _____

9-69-6

© Glencoe/McGraw-Hill 513 Glencoe Geometry

Less

on

9-6

Pre-Activity How do vectors help a pilot plan a flight?

Read the introduction to Lesson 9-6 at the top of page 498 in your textbook.

Why do pilots often head their planes in a slightly different direction fromtheir destination?

Reading the Lesson1. Supply the missing words or phrases to complete the following sentences.

a. A is a directed segment representing a quantity that has bothmagnitude and direction.

b. The length of a vector is called its .

c. Two vectors are parallel if and only if they have the same or direction.

d. A vector is in if it is drawn with initial point at the origin.

e. Two vectors are equal if and only if they have the same and the

same .

f. The sum of two vectors is called the .

g. A vector is written in if it is expressed as an ordered pair.

h. The process of multiplying a vector by a constant is called .

2. Write each vector described below in component form.

a. a vector in standard position with endpoint (a, b)

b. a vector with initial point (a, b) and endpoint (c, d)

c. a vector in standard position with endpoint (�3, 5)

d. a vector with initial point (2, �3) and endpoint (6, �8)

e. a� � b� if a� � ��3, 5� and b� � �6, �4�

f. 5u� if u� � �8, �6�

g. ��13�v� if v� � ��15, 24�

h. 0.5u� � 1.5v� if u� � �10, �10� and v� � ��8, 6�

Helping You Remember3. A good way to remember a new mathematical term is to relate it to a term you already

know. You learned about scale factors when you studied similarity and dilations. How is theidea of a scalar related to scale factors?

Skills PracticeVectors

NAME ______________________________________________ DATE ____________ PERIOD _____

9-69-6

© Glencoe/McGraw-Hill 511 Glencoe Geometry

Less

on

9-6

Write the component form of each vector.

1. 2.

Find the magnitude and direction of RS� for the given coordinates. Round to thenearest tenth.

3. R(2, �3), S(4, 9) 4. R(0, 2), S(3, 12)

5. R(5, 4), S(�3, 1) 6. R(1, 5), S(�4, �6)

Graph the image of each figure under a translation by the given vector(s).

7. �ABC with vertices A(�4, 3), B(�1, 4), 8. trapezoid with vertices T(�4, �2),C(�1, 1); t� � �4, �3� R(�1, �2), S(�2, �3), Y(�3, �3); a� � �3, 1�

and b� � �2, 4�

Find the magnitude and direction of each resultant for the given vectors.

9. y� � �7, 0�, z� � �0, 6� 10. b� � �3, 2�, c� � ��2, 3�

S�Y�

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SY

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y

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B

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x

y

O

x

y

O

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x

y

OC(1, –1)

E(4, 3)

Reading to Learn MathematicsTransformations with Matrices

NAME ______________________________________________ DATE ____________ PERIOD _____

9-79-7

© Glencoe/McGraw-Hill 519 Glencoe Geometry

Less

on

9-7

Pre-Activity How can matrices be used to make movies?

Read the introduction to Lesson 9-7 at the top of page 506 in your textbook.

• What kind of transformation should be used to move a polygon?

• What kind of transformation should be used to resize a polygon?

Reading the Lesson1. Write a vertex matrix for each figure.

a. �ABC b. parallelogram ABCD

2. Match each transformation from the first column with the corresponding matrix fromthe second or third column. In each case, the vertex matrix for the preimage of a figureis multiplied on the left by one of the matrices below to obtain the image of the figure.All rotations listed are counterclockwise through the origin. (Some matrices may be usedmore than once or not at all.)

a. reflection over the y-axis i. v.b. 90° rotationc. reflection over the line y � x ii. vi.d. 270° rotatione. reflection over the origin iii. vii.f. 180° rotationg. reflection over the x-axis iv. viii.h. 360° rotation

Helping You Remember3. How can you remember or quickly figure out the matrices for the transformations in

Exercise 2?

0 �11 0

0 �1�1 0

1 00 �1

0 11 0

�1 0 0 1

�1 0 0 �1

0 1�1 0

1 00 1

B C

A D x

y

O

B

C

A

x

y

O

Study Guide and InterventionTransformations with Matrices

NAME ______________________________________________ DATE ____________ PERIOD _____

9-79-7

© Glencoe/McGraw-Hill 515 Glencoe Geometry

Less

on

9-7

Translations and Dilations A vector can be represented by the ordered pair �x, y� or

by the column matrix . When the ordered pairs for all the vertices of a polygon are

placed together, the resulting matrix is called the vertex matrix for the polygon.

For �ABC with A(�2, 2), B(2, 1), and C(�1, �1), the vertex

matrix for the triangle is .

For �ABC above, use a matrix to find the coordinates of thevertices of the image of �ABC under the translation (x, y) → (x � 3, y � 1).To translate the figure 3 units to the right, add 3 to each x-coordinate. To translate thefigure 1 unit down, add �1 to each y-coordinate.

Vertex Matrix Translation Vertex Matrixof �ABC Matrix of �A�B�C�

� �

The coordinates are A�(1, 1), B�(5, 0), and C�(2, �2).

For �ABC above, use a matrix to find the coordinates of the verticesof the image of �ABC for a dilation centered at the origin with scale factor 3.

Scale Vertex Matrix Vertex MatrixFactor of �ABC of �A�B�C�

3 �

The coordinates are A�(�6, 6), B�(6, 3), and C�(�3, �3).

Use a matrix to find the coordinates of the vertices of the image of each figureunder the given translations or dilations.

1. �ABC with A(3, 1), B(�2, 4), C(�2, �1); (x, y) → (x � 1, y � 2)

2. parallelogram RSTU with R(�4, �2), S(�3, 1), T(3, 4), U(2, 1); (x, y) → (x � 4, y � 3)

3. rectangle PQRS with P(4, 0), Q(3, �3), R(�3, �1), S(�2, 2); (x, y) → (x � 2, y � 1)

4. �ABC with A(�2, �1), B(�2, �3), C(2, �1); dilation centered at the origin with scalefactor 2

5. parallelogram RSTU with R(4, �2), S(�4, �1), T(�2, 3), U(6, 2); dilation centered at theorigin with scale factor 1.5

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�2 2 �1 2 1 �1

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x y

ExercisesExercises

Example 1Example 1

Example 2Example 2

© Glencoe/McGraw-Hill 516 Glencoe Geometry

Reflections and Rotations When you reflect an image, one way to find thecoordinates of the reflected vertices is to multiply the vertex matrix of the object by areflection matrix. To perform more than one reflection, multiply by one reflection matrixto find the first image. Then multiply by the second matrix to find the final image. Thematrices for reflections in the axes, the origin, and the line y � x are shown below.

For a reflection in the: x-axis y-axis origin line y � x

Multiply the vertex matrix by:

�ABC has vertices A(�2, 3), B(1, 4), and C(3, 0). Use a matrix to find the coordinates of the vertices of the image of �ABC after a reflection in the x-axis.To reflect in the x-axis, multiply the vertex matrix of �ABC by thereflection matrix for the x-axis.

Reflection Matrix Vertex Matrix Vertex Matrix for x-axis of �ABC of �A’B’C’

Use a matrix to find the coordinates of the vertices of the image of each figureunder the given reflection.

1. �ABC with A(�3, 2), B(�1, 3), C(1, 0); reflection in the x-axis

2. �XYZ with X(2, �1), Y(4, �3), Z(�2, 1); reflection in the y-axis

3. �ABC with A(3, 4), B(�1, 0), C(�2, 4); reflection in the origin

4. parallelogram RSTU with R(�3, 2), S(3, 2), T(5, �1), U(�1, �1); reflection in the line y � x

5. �ABC with A(2, 3), B(�1, 2), C(1, �1); reflection in the origin, then reflection in the liney � x

6. parallelogram RSTU with R(0, 2), S(4, 2), T(3, �2), U(�1, �2); reflection in the x-axis,then reflection in the y-axis

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x

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A�B�

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C

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�1 0 0 �1

�1 0 0 1

1 00 �1

Study Guide and Intervention (continued)

Transformations with Matrices

NAME ______________________________________________ DATE ____________ PERIOD _____

9-79-7

ExampleExample

ExercisesExercises

© Glencoe/McGraw-Hill A4 Glencoe Geometry

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no.

a.a

squ

are

4;ye

sb

.an

iso

scel

es t

rian

gle

(not

equ

ilat

eral

) 1;

no

c.a

regu

lar

hex

agon

6;

yes

d.a

n i

sosc

eles

tra

pezo

id 1

;n

oe.

a re

ctan

gle

(not

a s

quar

e) 2

;ye

sf.

the

lett

er E

1;

no

Hel

pin

g Y

ou

Rem

emb

er4.

A g

ood

way

to

rem

embe

r a

new

geo

met

ric

term

is

to r

elat

e th

e w

ord

or i

ts p

arts

to

geom

etri

c te

rms

you

alr

eady

kn

ow.L

ook

up

the

orig

ins

of t

he

two

part

s of

th

e w

ord

isom

etry

in y

our

dict

ion

ary.

Exp

lain

th

e m

ean

ing

of e

ach

par

t an

d gi

ve a

ter

m y

oual

read

y kn

ow t

hat

sh

ares

th

e or

igin

of

that

par

t.S

amp

le a

nsw

er:T

he

firs

t p

art

com

es f

rom

iso

s,w

hic

h m

ean

s eq

ual

,as

in is

osc

eles

.Th

e se

con

d p

art

com

es f

rom

met

ron

,wh

ich

mea

ns

mea

sure

,as

in g

eom

etry

.

A�

B�

C�

D�

E�

AB

CD

E

x

y

O

R�

S�

T�

RS

P

Tn

A�

B�

C�

D�

A

BC D

©G

lenc

oe/M

cGra

w-H

ill48

4G

lenc

oe G

eom

etry

Ref

lect

ion

s in

th

e C

oo

rdin

ate

Pla

ne

Stu

dy

the

dia

gram

at

the

righ

t.It

sh

ows

how

th

e tr

ian

gle

AB

Cis

map

ped

on

to t

rian

gle

XY

Zb

y th

etr

ansf

orm

atio

n (

x,y)

→(�

x�

6,y)

.Not

ice

that

�X

YZ

is t

he

refl

ecti

on i

mag

e w

ith

res

pec

t to

th

e ve

rtic

al

lin

e w

ith

eq

uat

ion

x�

3.

1.P

rove

th

at t

he

vert

ical

lin

e w

ith

equ

atio

n x

�3

is t

he

perp

endi

cula

r bi

sect

or o

f th

e se

gmen

t w

ith

en

dpoi

nts

(x

,y)

and

(�x

�6,

y).(

Hin

t:U

se t

he

mid

poin

t fo

rmu

la.)

Mid

po

int

���x

�(�

2x�

6)�

,�y

� 2y

��o

r (3

,y)

Th

e se

gm

ent

join

ing

(x,

y)

and

(�

x�

6,y

) is

h

ori

zon

tal a

nd

hen

ce is

per

pen

dic

ula

r to

th

e ve

rtic

al li

ne.

2.E

very

tra

nsf

orm

atio

n o

f th

e fo

rm (

x,y)

→(�

x�

2h

,y)

is

a re

flec

tion

wit

h r

espe

ct t

o th

e ve

rtic

al l

ine

wit

h e

quat

ion

x

�h

.Wh

at k

ind

of t

ran

sfor

mat

ion

is

(x,y

) →

(x,�

y�

2k)

?

refl

ecti

on

wit

h r

esp

ect

to t

he

ho

rizo

nta

l lin

e w

ith

eq

uat

ion

y�

k

Dra

w t

he

tran

sfor

mat

ion

im

age

for

each

fig

ure

an

d t

he

give

n

tran

sfor

mat

ion

.Is

it a

ref

lect

ion

tra

nsf

orm

atio

n?

If s

o,w

ith

re

spec

t to

wh

at l

ine?

3.(x

,y)

→(�

x�

4,y)

4.(x

,y)

→(x

,�y

�8)

yes;

x�

�2

yes;

y�

4

x

y

Ox

y

O

x �

3

A

B

C

X

Y

Z

(x, y

) → (�

x �

6, y

)

x

y

O

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-1

9-1

Answers (Lesson 9-1)

© Glencoe/McGraw-Hill A7 Glencoe Geometry

An

swer

s

Readin

g t

o L

earn

Math

em

ati

csTr

ansl

atio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-2

9-2

©G

lenc

oe/M

cGra

w-H

ill48

9G

lenc

oe G

eom

etry

Lesson 9-2

Pre-

Act

ivit

yH

ow a

re t

ran

slat

ion

s u

sed

in

a m

arch

ing

ban

d s

how

?

Rea

d th

e in

trod

uct

ion

to

Les

son

9-2

at

the

top

of p

age

470

in y

our

text

book

.

How

do

ban

d di

rect

ors

get

the

mar

chin

g ba

nd

to m

ain

tain

th

e sh

ape

of t

he

figu

re t

hey

ori

gin

ally

for

med

?S

amp

le a

nsw

er:T

he

ban

d p

ract

ices

mar

chin

g in

un

iso

n,w

ith

eve

ryo

ne

mak

ing

iden

tica

l mov

es a

tth

e sa

me

tim

e.R

ead

ing

th

e Le

sso

n1.

Un

derl

ine

the

corr

ect

wor

d or

ph

rase

to

form

a t

rue

stat

emen

t.a.

All

ref

lect

ion

s an

d tr

ansl

atio

ns

are

(opp

osit

es/is

omet

ries

/equ

ival

ent)

.b

.T

he

prei

mag

e an

d im

age

of a

fig

ure

un

der

a re

flec

tion

in

a l

ine

hav

e (t

he

sam

e or

ien

tati

on/o

ppos

ite

orie

nta

tion

s).

c.T

he

prei

mag

e an

d im

age

of a

fig

ure

un

der

a tr

ansl

atio

n h

ave

(th

e sa

me

orie

nta

tion

/opp

osit

e or

ien

tati

ons)

.d

.T

he

resu

lt o

f su

cces

sive

ref

lect

ion

s ov

er t

wo

para

llel

lin

es i

s a

(ref

lect

ion

/rot

atio

n/t

ran

slat

ion

).e.

Col

lin

eari

ty (

is/i

s n

ot)

pres

erve

d by

tra

nsl

atio

ns.

f.T

he

tran

slat

ion

(x,

y) →

(x�

a,y

�b)

sh

ifts

eve

ry p

oin

t a

un

its

(hor

izon

tall

y/ve

rtic

ally

) an

d y

un

its

(hor

izon

tall

y/ve

rtic

ally

).

2.F

ind

the

imag

e of

eac

h p

reim

age

un

der

the

indi

cate

d tr

ansl

atio

n.

a.(x

,y);

5 u

nit

s ri

ght

and

3 u

nit

s u

p(x

�5,

y�

3)b

.(x

,y);

2 u

nit

s le

ft a

nd

4 u

nit

s do

wn

(x�

2,y

�4)

c.(x

,y);

1 u

nit

lef

t an

d 6

un

its

up

(x�

1,y

�6)

d.

(x,y

);7

un

its

righ

t(x

�7,

y)e.

(4,�

3);3

un

its

up

(4,0

)f.

(�5,

6);3

un

its

righ

t an

d 2

un

its

dow

n(�

2,4)

g.(�

7,5)

;7 u

nit

s ri

ght

and

5 u

nit

s do

wn

(0,0

)h

.(�

9,�

2);1

2 u

nit

s ri

ght

and

6 u

nit

s do

wn

(3,�

8)

3.�

RS

Th

as v

erti

ces

R(�

3,3)

,S(0

,�2)

,an

d T

(2,1

).G

raph

�R

ST

and

its

imag

e �

R�S

�T�

unde

r th

e tr

ansl

atio

n (x

,y)

→(x

�3,

y�

2).

Lis

t th

e co

ordi

nat

es o

f th

e ve

rtic

es o

f th

e im

age.

R�(

0,1)

,S�(

3,�

4),T

�(5,

�1)

Hel

pin

g Y

ou

Rem

emb

er4.

A g

ood

way

to

rem

embe

r a

new

mat

hem

atic

al t

erm

is

to r

elat

e it

to

an e

very

day

mea

ning

of t

he

sam

e w

ord.

How

is

the

mea

nin

g of

tra

nsl

atio

nin

geo

met

ry r

elat

ed t

o th

e id

ea o

ftr

ansl

atio

nfr

om o

ne

lan

guag

e to

an

oth

er?

Sam

ple

an

swer

:Wh

en y

ou

tra

nsl

ate

fro

m o

ne

lan

gu

age

to a

no

ther

,yo

u c

arry

ove

rth

e m

ean

ing

fro

m o

ne

lan

gu

age

to a

no

ther

.Wh

en y

ou

tra

nsl

ate

a g

eom

etri

c fig

ure

,yo

u c

arry

over

the

figu

re f

rom

on

e p

osi

tion

to

an

oth

er w

itho

ut

chan

gin

g it

s b

asic

R�

S�

T�

R

S

T

x

y

O

©G

lenc

oe/M

cGra

w-H

ill49

0G

lenc

oe G

eom

etry

Tran

slat

ion

s in

Th

e C

oo

rdin

ate

Pla

ne

You

can

use

alg

ebra

ic d

escr

ipti

ons

of r

efle

ctio

ns

to s

how

th

atth

e co

mp

osit

e of

tw

o re

flec

tion

s w

ith

res

pec

t to

par

alle

l li

nes

is

a tr

ansl

atio

n (

that

is,

a sl

ide)

.

1.S

upp

ose

aan

d b

are

two

diff

eren

t re

al n

um

bers

.Let

San

d T

be t

he

foll

owin

g re

flec

tion

s.

S:(

x,y)

→(�

x�

2a,

y)T

:(x,

y) →

(�x

�2

b,y)

Sis

ref

lect

ion

wit

h r

espe

ct t

o th

e li

ne

wit

h e

quat

ion

x�

a,an

d T

isre

flec

tion

wit

h r

espe

ct t

o th

e li

ne

wit

h e

quat

ion

x�

b.

a.F

ind

an a

lgeb

raic

des

crip

tion

(si

mil

ar t

o th

ose

abov

e fo

r S

and

T)

to d

escr

ibe

the

com

posi

te t

ran

sfor

mat

ion

“S

foll

owed

by

T.”

(x,y

) →

(x�

2 (b

�a)

,y)

b.F

ind

an a

lgeb

raic

des

crip

tion

for

th

e co

mpo

site

tra

nsf

orm

atio

n“T

foll

owed

by

S.”

(x,y

) →

(x�

2 (a

�b

),y

)

2.T

hin

k ab

out

the

resu

lts

you

obt

ain

ed i

n E

xerc

ise

1.W

hat

do

they

tell

you

abo

ut

how

th

e di

stan

ce b

etw

een

tw

o pa

rall

el l

ines

is

rela

ted

to t

he

dist

ance

bet

wee

n a

pre

imag

e an

d im

age

poin

t fo

r a

com

posi

te o

f re

flec

tion

s w

ith

res

pect

to

thes

e li

nes

?

Th

e d

ista

nce

bet

wee

n a

pre

imag

e an

d it

s im

age

po

int

istw

ice

the

dis

tan

ce b

etw

een

th

e p

aral

lel l

ines

.

3.Il

lust

rate

you

r an

swer

s to

Exe

rcis

es 1

an

d 2

wit

h s

ketc

hes

.Use

ase

para

te s

hee

t if

nec

essa

ry.

See

stu

den

ts’w

ork

.

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-2

9-2

Answers (Lesson 9-2)

© Glencoe/McGraw-Hill A10 Glencoe Geometry

Readin

g t

o L

earn

Math

em

ati

csR

ota

tio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-3

9-3

©G

lenc

oe/M

cGra

w-H

ill49

5G

lenc

oe G

eom

etry

Lesson 9-3

Pre-

Act

ivit

yH

ow d

o so

me

amu

sem

ent

rid

es i

llu

stra

te r

otat

ion

s?

Rea

d th

e in

trod

uct

ion

to

Les

son

9-3

at

the

top

of p

age

476

in y

our

text

book

.

Wh

at a

re t

wo

way

s th

at e

ach

car

rot

ates

?

Eac

h c

ar s

pin

s ar

ou

nd

its

ow

n c

ente

r an

d e

ach

car

ro

tate

sar

ou

nd

a p

oin

t in

th

e ce

nte

r o

f th

e ci

rcu

lar

trac

k.

Rea

din

g t

he

Less

on

1.L

ist

all

of t

he

foll

owin

g ty

pes

of t

ran

sfor

mat

ion

s th

at s

atis

fy e

ach

des

crip

tion

:ref

lect

ion

,tr

ansl

atio

n,r

otat

ion

.a.

Th

e tr

ansf

orm

atio

n i

s an

iso

met

ry.

refl

ecti

on

,tra

nsl

atio

n,r

ota

tio

nb

.T

he

tran

sfor

mat

ion

pre

serv

es t

he

orie

nta

tion

of

a fi

gure

.tr

ansl

atio

n,r

ota

tio

nc.

Th

e tr

ansf

orm

atio

n i

s th

e co

mpo

site

of

succ

essi

ve r

efle

ctio

ns

over

tw

o in

ters

ecti

ng

lin

es.

rota

tio

nd

.T

he

tran

sfor

mat

ion

is

the

com

posi

te o

f su

cces

sive

ref

lect

ion

s ov

er t

wo

para

llel

li

nes

.tr

ansl

atio

ne.

A s

peci

fic

tran

sfor

mat

ion

is

defi

ned

by

a fi

xed

poin

t an

d a

spec

ifie

d an

gle.

rota

tio

nf.

A s

peci

fic

tran

sfor

mat

ion

is

defi

ned

by

a fi

xed

poin

t,a

fixe

d li

ne,

or a

fix

ed p

lan

e.re

flec

tio

ng.

A s

peci

fic

tran

sfor

mat

ion

is

defi

ned

by

(x,y

) →

(x�

a,x

�b)

,for

fix

ed v

alu

es o

f a

and

b.tr

ansl

atio

nh

.T

he

tran

sfor

mat

ion

is

also

cal

led

a sl

ide.

tran

slat

ion

i.T

he

tran

sfor

mat

ion

is

also

cal

led

a fl

ip.

refl

ecti

on

j.T

he

tran

sfor

mat

ion

is

also

cal

led

a tu

rn.

rota

tio

n

2.D

eter

min

e th

e or

der

and

mag

nit

ude

of

the

rota

tion

al s

ymm

etry

for

eac

h f

igu

re.

a.b

.

ord

er 3

;m

agn

itu

de

120°

ord

er 2

;m

agn

itu

de

180°

c.d

.

ord

er 5

;m

agn

itu

de

72°

ord

er 8

;m

agn

itu

de

45°

Hel

pin

g Y

ou

Rem

emb

er

3.W

hat

is

an e

asy

way

to

rem

embe

r th

e or

der

and

mag

nit

ude

of

the

rota

tion

al s

ymm

etry

of a

reg

ula

r po

lygo

n?

Sam

ple

an

swer

:Th

e o

rder

is t

he

sam

e as

th

e n

um

ber

of

sid

es.T

o f

ind

th

em

agn

itu

de,

div

ide

360

by t

he

nu

mb

er o

f si

des

.

©G

lenc

oe/M

cGra

w-H

ill49

6G

lenc

oe G

eom

etry

Fin

din

g t

he

Cen

ter

of

Ro

tati

on

Su

ppos

e yo

u a

re t

old

that

�X

�Y�Z

�is

th

e ro

tati

on i

mag

e of

�X

YZ

,bu

t yo

u a

re n

ot t

old

wh

ere

the

cen

ter

of r

otat

ion

is

nor

th

e m

easu

re

of t

he

angl

e of

rot

atio

n.C

an y

ou f

ind

them

? Ye

s,yo

u c

an.C

onn

ect

two

pair

s of

cor

resp

ondi

ng

vert

ices

wit

h s

egm

ents

.In

th

e fi

gure

,th

e se

gmen

ts Y

Y�

and

ZZ

�ar

e u

sed.

Dra

w t

he

perp

endi

cula

r bi

sect

ors,

�an

d m

,of

thes

ese

gmen

ts.T

he

poin

t C

wh

ere

�an

d m

inte

rsec

t is

th

e ce

nte

r of

rot

atio

n.

1.H

ow c

an y

ou f

ind

the

mea

sure

of

the

angl

e of

rot

atio

n i

n t

he

figu

re a

bove

?D

raw

�X

CX

�(�

YC

Y�

or

�Z

CZ

�w

ou

ld

also

do

) an

d m

easu

re it

wit

h a

pro

trac

tor.

Loc

ate

the

cen

ter

of r

otat

ion

for

th

e ro

tati

on t

hat

map

s W

XY

Zon

to W

�X�Y

�Z�.

Th

en f

ind

th

e m

easu

re o

f th

e an

gle

of r

otat

ion

.

2.3.

Th

e se

gm

ents

stu

den

ts c

ho

ose

to

bis

ect

may

var

y.S

ee s

tud

ents

’wo

rk.

Z

Z�

W

W�

X�

X

Y

Y�

cen

ter

of

rota

tio

n

ang

le o

fro

tati

on

:ab

ou

t 11

0

Z�

Z

W

W�

X�

X

Y�

Y

cen

ter

of

rota

tio

n

ang

le o

fro

tati

on

:ab

ou

t 10

0

Z�

Z

C

X�

X

Y�

Y

m�

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-3

9-3

Answers (Lesson 9-3)

© Glencoe/McGraw-Hill A8 Glencoe Geometry

Stu

dy G

uid

e a

nd I

nte

rven

tion

Ro

tati

on

s

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-3

9-3

©G

lenc

oe/M

cGra

w-H

ill49

1G

lenc

oe G

eom

etry

Lesson 9-3

Dra

w R

ota

tio

ns

A t

ran

sfor

mat

ion

cal

led

a ro

tati

ontu

rns

a fi

gure

th

rou

gh a

spe

cifi

edan

gle

abou

t a

fixe

d po

int

call

ed t

he

cen

ter

of r

otat

ion

.To

fin

d th

e im

age

of a

rot

atio

n,o

ne

way

is

to u

se a

pro

trac

tor.

An

oth

er w

ay i

s to

ref

lect

a f

igu

re t

wic

e,in

tw

o in

ters

ecti

ng

lin

es.

�A

BC

has

ver

tice

s A

(2,1

),B

(3,4

),an

d

C(5

,1).

Dra

w t

he

imag

e of

�A

BC

un

der

a r

otat

ion

of

90°

cou

nte

rclo

ckw

ise

abou

t th

e or

igin

.•

Fir

st d

raw

�A

BC

.Th

en d

raw

a s

egm

ent

from

O,t

he

orig

in,

to p

oin

t A

.•

Use

a p

rotr

acto

r to

mea

sure

90°

cou

nte

rclo

ckw

ise

wit

h O �

A�as

on

e si

de.

•D

raw

OR

� �� .

•U

se a

com

pass

to

copy

O �A�

onto

OR

��� .

Nam

e th

e se

gmen

t O�

A���.

•R

epea

t w

ith

seg

men

ts f

rom

th

e or

igin

to

poin

ts B

and

C.

Fin

d t

he

imag

e of

�A

BC

un

der

ref

lect

ion

in

lin

es m

and

n.

Fir

st r

efle

ct �

AB

Cin

lin

e m

.Lab

el t

he

imag

e �

A�B

�C�.

Ref

lect

�A�

B�C

�in

lin

e n.

Lab

el t

he

imag

e �

A�B

�C�.

�A

�B�C

�is

a r

otat

ion

of

�A

BC

.Th

e ce

nte

r of

rot

atio

n i

s th

ein

ters

ecti

on o

f li

nes

man

d n.

Th

e an

gle

of r

otat

ion

is

twic

e th

em

easu

re o

f th

e ac

ute

an

gle

form

ed b

y m

and

n.

Dra

w t

he

rota

tion

im

age

of e

ach

fig

ure

90°

in t

he

give

n d

irec

tion

ab

out

the

cen

ter

poi

nt

and

lab

el t

he

coor

din

ates

.

1.P�

Q�w

ith

en

dpoi

nts

P(�

1,�

2)

2.�

PQ

Rw

ith

ver

tice

s P

(�2,

�3)

,Q(2

,�1)

,an

d Q

(1,3

) co

un

terc

lock

wis

e an

d R

(3,2

) cl

ockw

ise

abou

t th

e po

int

T(1

,1)

abou

t th

e or

igin

Fin

d t

he

rota

tion

im

age

of e

ach

fig

ure

by

refl

ecti

ng

it i

n l

ine

man

d t

hen

in

lin

e n

.

3.4.

mn

B�

C�

A�

AB

C

B�

C�

A�

mn

Q�

P�

Q

PQ

P�

x

yP

Q�

R�

P

Q

RT

x

y

P�

Q�

P

Q

m

n

A� B

�C

A�

B�

C�

B

C

A

x

y

O

A�

B�

C�

A

B

C

R

Exer

cises

Exer

cises

Exam

ple1

Exam

ple1

Exam

ple2

Exam

ple2

©G

lenc

oe/M

cGra

w-H

ill49

2G

lenc

oe G

eom

etry

Ro

tati

on

al S

ymm

etry

Wh

en t

he

figu

re a

t th

e ri

ght

is r

otat

ed

abou

t po

int

Pby

120

°or

240

°,th

e im

age

look

s li

ke t

he

prei

mag

e.T

he

figu

re h

as r

otat

ion

al s

ymm

etry

,wh

ich

mea

ns

it c

an b

e ro

tate

d le

ss

than

360

°ab

out

a po

int

and

the

prei

mag

e an

d im

age

appe

ar t

o be

th

e sa

me.

Th

e fi

gure

has

rot

atio

nal

sym

met

ry o

f or

der

3 be

cau

se t

her

e ar

e 3

rota

tion

s le

ss t

han

360

°(0

°,12

0°,2

40°)

th

at p

rodu

ce a

n i

mag

e th

at

is t

he

sam

e as

th

e or

igin

al.T

he

mag

nit

ud

eof

th

e ro

tati

onal

sym

met

ry

for

a fi

gure

is

360

degr

ees

divi

ded

by t

he

orde

r.F

or t

he

figu

re a

bove

,th

e ro

tati

onal

sym

met

ry h

as m

agn

itu

de 1

20 d

egre

es.

Iden

tify

th

e or

der

an

d m

agn

itu

de

of t

he

rota

tion

al

sym

met

ry o

f th

e d

esig

n a

t th

e ri

ght.

Th

e de

sign

has

rot

atio

nal

sym

met

ry a

bou

t th

e ce

nte

r po

int

for

rota

tion

s of

0°,

45°,

90°,

135°

,180

°,22

5°,2

70°,

and

315°

.

Th

ere

are

eigh

t ro

tati

ons

less

th

an 3

60 d

egre

es,s

o th

e or

der

of i

ts

rota

tion

al s

ymm

etry

is

8.T

he

quot

ien

t 36

0 �

8 is

45,

so t

he

mag

nit

ude

of

its

rot

atio

nal

sym

met

ry i

s 45

deg

rees

.

Iden

tify

th

e or

der

an

d m

agn

itu

de

of t

he

rota

tion

al s

ymm

etry

of

each

fig

ure

.

1.a

squ

are

2.a

regu

lar

40-g

on

ord

er:

4;m

agn

itu

de:

90°

ord

er:

40;

mag

nit

ud

e:9°

3.4.

ord

er:

2;m

agn

itu

de:

180°

ord

er:

5;m

agn

itu

de:

72°

5.6.

ord

er:

16;

mag

nit

ud

e:22

.5°

ord

er:

3;m

agn

itu

de:

120°

P

Stu

dy G

uid

e a

nd I

nte

rven

tion

(con

tinued

)

Ro

tati

on

s

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-3

9-3

Exer

cises

Exer

cises

Exam

ple

Exam

ple

Answers (Lesson 9-3)

© Glencoe/McGraw-Hill A13 Glencoe Geometry

An

swer

s

Readin

g t

o L

earn

Math

em

ati

csTe

ssel

atio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-4

9-4

©G

lenc

oe/M

cGra

w-H

ill50

1G

lenc

oe G

eom

etry

Lesson 9-4

Pre-

Act

ivit

yH

ow a

re t

esse

llat

ion

s u

sed

in

art

?

Rea

d th

e in

trod

uct

ion

to

Les

son

9-4

at

the

top

of p

age

483

in y

our

text

book

.

•In

th

e pa

tter

n s

how

n i

n t

he

pict

ure

in

you

r te

xtbo

ok,h

ow m

any

smal

leq

uil

ater

al t

rian

gles

mak

e u

p on

e re

gula

r h

exag

on?

6•

In t

his

pat

tern

,how

man

y fi

sh m

ake

up

one

equ

ilat

eral

tri

angl

e?1�

1 2�

Rea

din

g t

he

Less

on

1.U

nde

rlin

e th

e co

rrec

t w

ord,

phra

se,o

r n

um

ber

to f

orm

a t

rue

stat

emen

t.

a.A

tes

sell

atio

n i

s a

patt

ern

th

at c

over

s a

plan

e w

ith

th

e sa

me

figu

re o

r se

t of

fig

ure

s so

that

th

ere

are

no

(con

gru

ent

angl

es/o

verl

appi

ng

or e

mpt

y sp

aces

/rig

ht

angl

es).

b.

A t

esse

llat

ion

th

at u

ses

only

on

e ty

pe o

f re

gula

r po

lygo

n i

s ca

lled

a(u

nif

orm

/reg

ula

r/se

mi-

regu

lar)

tes

sell

atio

n.

c.T

he

sum

of

the

mea

sure

s of

th

e an

gles

at

any

vert

ex i

n a

ny

tess

ella

tion

is

(90/

180/

360)

.

d.

A t

esse

llat

ion

th

at c

onta

ins

the

sam

e ar

ran

gem

ent

of s

hap

es a

nd

angl

es a

t ev

ery

vert

ex i

s ca

lled

a (

un

ifor

m/r

egu

lar/

sem

i-re

gula

r) t

esse

llat

ion

.

e.In

a r

egu

lar

tess

ella

tion

mad

e u

p of

hex

agon

s,th

ere

are

(3/4

/6)

hex

agon

s m

eeti

ng

atea

ch v

erte

x,an

d th

e m

easu

re o

f ea

ch o

f th

e an

gles

at

any

vert

ex i

s (6

0/90

/120

).

f.A

un

ifor

m t

esse

llat

ion

for

med

usi

ng

two

or m

ore

regu

lar

poly

gon

s is

cal

led

a(r

otat

ion

al/r

egu

lar/

sem

i-re

gula

r) t

esse

llat

ion

.

g.In

a r

egu

lar

tess

ella

tion

mad

e u

p of

tri

angl

es,t

her

e ar

e (3

/4/6

) tr

ian

gles

mee

tin

g at

each

ver

tex,

and

the

mea

sure

of

each

of

the

angl

es a

t an

y ve

rtex

is

(30/

60/1

20).

h.

If a

reg

ula

r te

ssel

lati

on i

s m

ade

up

of q

uad

rila

tera

ls,a

ll o

f th

e qu

adri

late

rals

mu

st b

eco

ngr

uen

t (r

ecta

ngl

es/p

aral

lelo

gram

s/sq

uar

es/t

rape

zoid

s).

2.W

rite

all

of

the

foll

owin

g w

ords

th

at d

escr

ibe

each

tes

sell

atio

n:u

nif

orm

,non

-un

ifor

m,

regu

lar,

sem

i-re

gula

r.

a.n

on

-un

iform

b.

un

iform

,sem

i-re

gu

lar

Hel

pin

g Y

ou

Rem

emb

er

3.O

ften

th

e ev

eryd

ay m

ean

ings

of

a w

ord

can

hel

p yo

u t

o re

mem

ber

its

mat

hem

atic

alm

ean

ing.

Loo

k u

p u

nif

orm

in y

our

dict

ion

ary.

How

can

its

eve

ryda

y m

ean

ings

hel

p yo

uto

rem

embe

r th

e m

ean

ing

of a

un

ifor

mte

ssel

lati

on?

Sam

ple

an

swer

:Th

ree

sim

ilar

mea

nin

gs

of

un

iform

are

unv

aryi

ng

,co

nsi

sten

t,an

d id

enti

cal.

In a

un

iform

tes

sella

tio

n,t

he

arra

ng

emen

t o

f sh

apes

an

d a

ng

les

at e

ach

vert

ex is

th

e sa

me.

Eac

h o

f th

e th

ree

ever

yday

mea

nin

gs

des

crib

es t

his

situ

atio

n.

©G

lenc

oe/M

cGra

w-H

ill50

2G

lenc

oe G

eom

etry

Po

lyg

on

al N

um

ber

sC

erta

in n

um

bers

rel

ated

to

regu

lar

poly

gon

s ar

e ca

lled

pol

ygon

al n

um

ber

s.T

he

char

tsh

ows

seve

ral

tria

ngu

lar,

squ

are,

and

pen

tago

nal

nu

mbe

rs.T

he

ran

kof

a p

olyg

on n

um

ber

is t

he

nu

mbe

r of

dot

s on

eac

h “

side

”of

th

e ou

ter

poly

gon

.For

exa

mpl

e,th

e pe

nta

gon

aln

um

ber

22 h

as a

ran

k of

4.

Pol

ygon

al n

um

bers

can

be

desc

ribe

d w

ith

for

mu

las.

For

exa

mpl

e,a

tria

ngu

lar

nu

mbe

r T

of r

ank

r ca

n b

e de

scri

bed

by T

��r(

r2�

1)�

.

An

swer

eac

h q

ues

tion

.

1.D

raw

a d

iagr

am t

o fi

nd

the

2.D

raw

a d

iagr

am t

o fi

nd

the

tria

ngu

lar

nu

mbe

r of

ran

k 5.

15pe

nta

gon

al n

um

ber

of r

ank

5.35

3.W

rite

a f

orm

ula

for

a s

quar

e n

um

ber

4.W

rite

a f

orm

ula

for

a p

enta

gon

alS

of r

ank

r.n

um

ber

Pof

ran

k r.

S�

r2P

��r(

3r2�

1)�

5.W

hat

is

the

ran

k of

th

e pe

nta

gon

al6.

Lis

t th

e h

exag

onal

nu

mbe

rs f

or r

anks

nu

mbe

r 70

?7

1 to

5.(

Hin

t:D

raw

a d

iagr

am.)

1,6,

15,2

8,45

Ran

k 1

Tria

ngle

13

610

14

916

15

1222

Squ

are

Pen

tago

n

Ran

k 2

Ran

k 3

Ran

k 4

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-4

9-4

Answers (Lesson 9-4)

© Glencoe/McGraw-Hill A11 Glencoe Geometry

An

swer

s

Stu

dy G

uid

e a

nd I

nte

rven

tion

Tess

ella

tio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-4

9-4

©G

lenc

oe/M

cGra

w-H

ill49

7G

lenc

oe G

eom

etry

Lesson 9-4

Reg

ula

r Te

ssel

lati

on

sA

pat

tern

th

at c

over

s a

plan

e w

ith

rep

eati

ng

copi

es o

f on

e or

mor

e fi

gure

s so

th

at t

her

e ar

e n

o ov

erla

ppin

g or

em

pty

spac

es i

s a

tess

ella

tion

.A r

egu

lar

tess

ella

tion

uses

onl

y on

e ty

pe o

f re

gula

r po

lygo

n.In

a t

esse

llat

ion,

the

sum

of

the

mea

sure

sof

the

ang

les

of t

he p

olyg

ons

surr

ound

ing

a ve

rtex

is 3

60.I

f a

regu

lar

poly

gon

has

an

in

teri

oran

gle

that

is

a fa

ctor

of

360,

then

th

e po

lygo

n w

ill

tess

ella

te.

regu

lar

tess

ella

tion

tess

ella

tion

Cop

ies

of a

reg

ular

hex

agon

C

opie

s of

a r

egul

ar p

enta

gon

can

form

a t

esse

llatio

n.ca

nnot

for

m a

tes

sella

tion.

Det

erm

ine

wh

eth

er a

reg

ula

r 16

-gon

tes

sell

ates

th

e p

lan

e.E

xpla

in.

If m

�1

is t

he

mea

sure

of

one

inte

rior

an

gle

of a

reg

ula

r po

lygo

n,t

hen

a f

orm

ula

for

m�

1

is m

�1

��18

0(n n

�2)

�.U

se t

he

form

ula

wit

h n

�16

.

m�

1��18

0(n n

�2)

��18

0(1 16 6

�2)

�15

7.5

Th

e va

lue

157.

5 is

not

a f

acto

r of

360

,so

the

16-g

on w

ill

not

tes

sell

ate.

Det

erm

ine

wh

eth

er e

ach

pol

ygon

tes

sell

ates

th

e p

lan

e.If

so,

dra

w a

sam

ple

fig

ure

.

1.sc

alen

e ri

ght

tria

ngl

eye

s2.

isos

cele

s tr

apez

oid

yes

Det

erm

ine

wh

eth

er e

ach

reg

ula

r p

olyg

on t

esse

llat

es t

he

pla

ne.

Exp

lain

.

3.sq

uar

e4.

20-g

on

Yes;

the

mea

sure

of

each

inte

rio

r N

o;

the

mea

sure

of

each

inte

rio

r an

gle

is 9

0,an

d 9

0 is

a f

acto

r an

gle

is 1

62,a

nd

162

is n

ot

a fa

cto

r o

f 36

0.o

f 36

0.

5.se

ptag

on6.

15-g

on

No

;th

e m

easu

re o

f ea

ch in

teri

or

No

;th

e m

easu

re o

f ea

ch in

teri

or

ang

le is

128

.6,a

nd

128

.6 is

no

t a

ang

le is

156

,an

d 1

56 is

no

t a

fact

or

fact

or

of

360.

of

360.

7.oc

tago

n8.

pen

tago

n

No

;th

e m

easu

re o

f ea

ch in

teri

or

No

;th

e m

easu

re o

f ea

ch in

teri

or

ang

le is

135

,an

d 1

35 is

no

t a

ang

le is

108

,an

d 1

08 is

no

t a

fact

or

fact

or

of

360.

of

360.

Exer

cises

Exer

cises

Exam

ple

Exam

ple

©G

lenc

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w-H

ill49

8G

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oe G

eom

etry

Tess

ella

tio

ns

wit

h S

pec

ific

Att

rib

ute

sA

tes

sell

atio

n p

atte

rn c

an c

onta

in a

ny

type

of p

olyg

on.I

f th

e ar

ran

gem

ent

of s

hap

es a

nd

angl

es a

t ea

ch v

erte

x in

th

e te

ssel

lati

on i

s th

esa

me,

the

tess

ella

tion

is

un

ifor

m.A

sem

i-re

gula

r te

ssel

lati

onis

a u

nif

orm

tes

sell

atio

nth

at c

onta

ins

two

or m

ore

regu

lar

poly

gon

s.

Det

erm

ine

wh

eth

er a

kit

e w

ill

tess

ella

te t

he

pla

ne.

If s

o,d

escr

ibe

the

tess

ella

tion

as

un

ifor

m,r

egu

lar,

sem

i-re

gula

r,or

not

un

ifor

m.

A k

ite

wil

l te

ssel

late

th

e pl

ane.

At

each

ver

tex

the

sum

of

th

e m

easu

res

is a

�b

�b

�c,

wh

ich

is

360.

Th

e te

ssel

lati

on i

s u

nif

orm

.

Det

erm

ine

wh

eth

er a

sem

i-re

gula

r te

ssel

lati

on c

an b

e cr

eate

d f

rom

eac

h s

et o

ffi

gure

s.If

so,

sket

ch t

he

tess

ella

tion

.Ass

um

e th

at e

ach

fig

ure

has

a s

ide

len

gth

of

1 u

nit

.

1.rh

ombu

s,eq

uil

ater

al t

rian

gle,

2.sq

uar

e an

d eq

uil

ater

al t

rian

gle

and

octa

gon

no

yes

Det

erm

ine

wh

eth

er e

ach

pol

ygon

tes

sell

ates

th

e p

lan

e.If

so,

des

crib

e th

ete

ssel

lati

on a

s u

nif

orm

,not

un

ifor

m,r

egu

lar,

or s

emi-

regu

lar.

3.re

ctan

gle

4.h

exag

on a

nd

squ

are

yes,

un

iform

no

c�a�

b� b�

c�c�

a�

a�b�

b� b�

c�a�

b� b�

c�a�

b� b�

c�a�

b� b�

b�

c�a�

b� b�

Stu

dy G

uid

e a

nd I

nte

rven

tion

(con

tinued

)

Tess

ella

tio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-4

9-4

Exer

cises

Exer

cises

Exam

ple

Exam

ple

Answers (Lesson 9-4)

© Glencoe/McGraw-Hill A15 Glencoe Geometry

An

swer

s

Skil

ls P

ract

ice

Dila

tio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-5

9-5

©G

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eom

etry

Lesson 9-5

Dra

w t

he

dil

atio

n i

mag

e of

eac

h f

igu

re w

ith

cen

ter

Can

d t

he

give

n s

cale

fac

tor.

1.r

�2

2.r

��1 4�

Fin

d t

he

mea

sure

of

the

dil

atio

n i

mag

e M�

��N���o

r of

th

e p

reim

age

M�N�

usi

ng

the

give

n s

cale

fac

tor.

3.M

N�

3,r

�3

4.M

�N�

�7,

r�

21

M�N

��

9M

N�

�1 3�

CO

OR

DIN

ATE

GEO

MET

RYF

ind

th

e im

age

of e

ach

pol

ygon

,giv

en t

he

vert

ices

,aft

era

dil

atio

n c

ente

red

at

the

orig

in w

ith

a s

cale

fac

tor

of 2

.Th

en g

rap

h a

dil

atio

n

cen

tere

d a

t th

e or

igin

wit

h a

sca

le f

acto

r of

�1 2� .

5.J

(2,4

),K

(4,4

),P

(3,2

)6.

D(�

2,0)

,G(0

,2),

F(2

,�2)

Det

erm

ine

the

scal

e fa

ctor

for

eac

h d

ilat

ion

wit

h c

ente

r C

.Det

erm

ine

wh

eth

er t

he

dil

atio

n i

s an

en

larg

emen

t,re

du

ctio

n,o

r co

ng

ruen

ce t

ran

sfor

ma

tion

.Th

e d

ash

edfi

gure

is

the

dil

atio

n i

mag

e.

7.8.

4;en

larg

emen

t1;

con

gru

ence

tra

nsf

orm

atio

n

CC

G�

F�

D�

G�

F�

D�

x

y

O

J�K

P�

J�

K�

P�

x

y

O

CC

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lenc

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ill50

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eom

etry

Dra

w t

he

dil

atio

n i

mag

e of

eac

h f

igu

re w

ith

cen

ter

Can

d t

he

give

n s

cale

fac

tor.

1.r

��3 2�

2.r

��2 3�

Fin

d t

he

mea

sure

of

the

dil

atio

n i

mag

e A�

��T���o

r of

th

e p

reim

age

A�T�

usi

ng

the

give

nsc

ale

fact

or.

3.A

T�

15,r

��3 5�

4.A

T�

30,r

��

�1 6�5.

A�T

��

12,r

��4 3�

A�T

��

9A

�T�

�5

AT

�9

CO

OR

DIN

ATE

GEO

MET

RYF

ind

th

e im

age

of e

ach

pol

ygon

,giv

en t

he

vert

ices

,aft

era

dil

atio

n c

ente

red

at

the

orig

in w

ith

a s

cale

fac

tor

of 2

.Th

en g

rap

h a

dil

atio

n

cen

tere

d a

t th

e or

igin

wit

h a

sca

le f

acto

r of

�1 2� .

6.A

(1,1

),C

(2,3

),D

(4,2

),E

(3,1

)7.

Q(�

1,�

1),R

(0,2

),S

(2,1

)

Det

erm

ine

the

scal

e fa

ctor

for

eac

h d

ilat

ion

wit

h c

ente

r C

.Det

erm

ine

wh

eth

er t

he

dil

atio

n i

s an

en

larg

emen

t,re

du

ctio

n,o

r co

ng

ruen

ce t

ran

sfor

ma

tion

.Th

e d

otte

dfi

gure

is

the

dil

atio

n i

mag

e.

8.�1 3� ;

red

uct

ion

9.2;

enla

rgem

ent

10.P

HO

TOG

RA

PHY

Est

ebe

enla

rged

a 4

-in

ch b

y 6-

inch

ph

otog

raph

by

a fa

ctor

of

�5 2� .W

hat

are

the

new

dim

ensi

ons

of t

he

phot

ogra

ph?

10 in

.by

15 in

.

CC

S�

Q�

R�

S�

Q�

R�

x

y

O

C�

D�

E�

A�

C�

D�

E�

A�

x

y

O

C

C

Pra

ctic

e (

Ave

rag

e)

Dila

tio

ns

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-5

9-5

Answers (Lesson 9-5)

© Glencoe/McGraw-Hill A16 Glencoe Geometry

Readin

g t

o L

earn

Math

em

ati

csD

ilati

on

s

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-5

9-5

©G

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eom

etry

Lesson 9-5

Pre-

Act

ivit

yH

ow d

o yo

u u

se d

ilat

ion

s w

hen

you

use

a c

omp

ute

r?

Rea

d th

e in

trod

uct

ion

to

Les

son

9-5

at

the

top

of p

age

490

in y

our

text

book

.

In a

ddit

ion

to

the

exam

ple

give

n i

n y

our

text

book

,giv

e tw

o ev

eryd

ayex

ampl

es o

f sc

alin

g an

obj

ect,

one

that

mak

es t

he

obje

ct l

arge

r an

d an

oth

erth

at m

akes

it

smal

ler.

Sam

ple

an

swer

:la

rger

:en

larg

ing

ap

ho

tog

rap

h;

smal

ler:

mak

ing

a s

cale

mo

del

of

a bu

ildin

gR

ead

ing

th

e Le

sso

n1.

Eac

h o

f th

e va

lues

of

rgi

ven

bel

ow r

epre

sen

ts t

he

scal

e fa

ctor

for

a d

ilat

ion

.In

eac

hca

se,d

eter

min

e w

het

her

th

e di

lati

on i

s an

en

larg

emen

t,a

red

uct

ion

,or

a co

ngr

uen

cetr

ansf

orm

atio

n.

a.r

�3

enla

rgem

ent

b.r

�0.

5re

du

ctio

nc.

r�

�0.

75re

du

ctio

nd

.r�

�1

con

gru

ence

tra

nsf

orm

atio

ne.

r�

�2 3�re

du

ctio

nf.

r�

��3 2�

enla

rgem

ent

g.r

��

1.01

enla

rgem

ent

h.r

�0.

999

red

uct

ion

2.D

eter

min

e w

het

her

eac

h s

ente

nce

is

alw

ays,

som

etim

es,o

r n

ever

tru

e.If

th

e se

nte

nce

is

not

alw

ays

tru

e,ex

plai

n w

hy.

Fo

r ex

pla

nat

ion

s,sa

mp

le a

nsw

ers

are

giv

en.

a.A

dil

atio

n r

equ

ires

a c

ente

r po

int

and

a sc

ale

fact

or.

alw

ays

b.

A d

ilat

ion

ch

ange

s th

e si

ze o

f a

figu

re.

So

met

imes

;if

th

e d

ilati

on

is a

con

gru

ence

tra

nsf

orm

atio

n,t

he

size

of

the

fig

ure

is u

nch

ang

ed.

c.A

dil

atio

n c

han

ges

the

shap

e of

a f

igu

re.

Nev

er;

all d

ilati

on

s p

rod

uce

sim

ilar

fig

ure

s,an

d s

imila

r fi

gu

res

hav

e th

e sa

me

shap

e.d

.T

he

imag

e of

a f

igu

re u

nde

r a

dila

tion

lie

s on

th

e op

posi

te s

ide

of t

he

cen

ter

from

th

epr

eim

age.

So

met

imes

;th

is is

on

ly t

rue

wh

en t

he

scal

e fa

cto

r is

neg

ativ

e.e.

A s

imil

arit

y tr

ansf

orm

atio

n i

s a

con

gru

ence

tra

nsf

orm

atio

n.

So

met

imes

;th

is is

tru

e o

nly

wh

en t

he

scal

e fa

cto

r is

1 o

r �

1.f.

Th

e ce

nte

r of

a d

ilat

ion

is

its

own

im

age.

alw

ays

g.A

dil

atio

n i

s an

iso

met

ry.

So

met

imes

;th

is is

tru

e o

nly

wh

en t

he

dila

tio

n is

a co

ng

ruen

ce t

ran

sfo

rmat

ion

.h

.T

he

scal

e fa

ctor

for

a d

ilat

ion

is

a po

siti

ve n

um

ber.

So

met

imes

;th

e sc

ale

fact

or

can

be

any

po

siti

ve o

r n

egat

ive

nu

mb

er.

i.D

ilat

ion

s pr

odu

ce s

imil

ar f

igu

res.

alw

ays

Hel

pin

g Y

ou

Rem

emb

er3.

A g

ood

way

to

rem

embe

r so

met

hin

g is

to

expl

ain

it

to s

omeo

ne

else

.Su

ppos

e th

at y

our

clas

smat

e L

ydia

is

hav

ing

trou

ble

un

ders

tan

din

g th

e re

lati

onsh

ip b

etw

een

sim

ilar

ity

tran

sfor

mat

ion

san

d co

ngr

uen

ce t

ran

sfor

mat

ion

s.H

ow c

an y

ou e

xpla

in t

his

to

her

?S

amp

le a

nsw

er:

A c

on

gru

ence

tra

nsf

orm

atio

n p

rese

rves

th

e si

ze a

nd

shap

e o

f a

fig

ure

,th

at is

,th

e im

age

is c

on

gru

ent

to t

he

pre

imag

e.A

sim

ilari

ty t

ran

sfo

rmat

ion

pre

serv

es t

he

shap

e o

f a

fig

ure

,th

at is

,th

eim

age

is s

imila

r to

th

e p

reim

age.

A s

imila

rity

tra

nsf

orm

atio

n is

aco

ng

ruen

ce t

ran

sfo

rmat

ion

if t

he

scal

e fa

cto

r is

1 o

r �

1.

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Sim

ilar

Cir

cles

You

may

be

surp

rise

d to

lea

rn t

hat

tw

o n

onco

ngr

uen

t ci

rcle

s th

at l

ie i

nth

e sa

me

plan

e an

d h

ave

no

com

mon

in

teri

or p

oin

ts c

an b

e m

appe

don

e on

to t

he

oth

er b

y m

ore

than

on

e di

lati

on.

1.H

ere

is d

iagr

am t

hat

su

gges

ts o

ne

way

to

m

ap a

sm

alle

r ci

rcle

on

to a

lar

ger

one

usi

ng

a di

lati

on.T

he

circ

les

are

give

n.T

he

lin

essu

gges

t h

ow t

o fi

nd

the

cen

ter

for

the

dila

tion

.Des

crib

e h

ow t

he

cen

ter

is f

oun

d.U

se s

egm

ents

in

th

e di

agra

m t

o n

ame

the

scal

e fa

ctor

.

Dra

w t

he

two

co

mm

on

ext

ern

alta

ng

ents

.Th

e p

oin

t w

her

e th

ey in

ters

ect

is t

he

cen

ter

of

a d

ilati

on

th

at m

aps

�A

on

to �

A�;

scal

e fa

cto

r �

�A A�M M�

�.

2.H

ere

is a

not

her

pai

r of

non

con

gru

ent

circ

les

wit

h n

o co

mm

onin

teri

or p

oin

t.F

rom

Exe

rcis

e 1,

you

kn

ow y

ou c

an l

ocat

e a

poin

t of

f to

th

e le

ft o

f th

e sm

alle

r ci

rcle

th

at i

s th

e ce

nte

r fo

r a

dila

tion

map

pin

g �

Con

to �

C�.

Fin

d an

oth

er c

ente

r fo

r an

oth

er d

ilat

ion

that

map

s �

Con

to �

C�.

Mar

k an

d la

bel

segm

ents

to

nam

e th

esc

ale

fact

or.

Fin

d t

he

inte

rsec

tio

n o

f th

e tw

o c

om

mo

n in

tern

al t

ang

ents

;sc

ale

fact

or:

��C C�X X

��

.

X

X�

C�

CO

A �

M�

M

AO

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-5

9-5

Answers (Lesson 9-5)

© Glencoe/McGraw-Hill A18 Glencoe Geometry

Skil

ls P

ract

ice

Vec

tors

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-6

9-6

©G

lenc

oe/M

cGra

w-H

ill51

1G

lenc

oe G

eom

etry

Lesson 9-6

Wri

te t

he

com

pon

ent

form

of

each

vec

tor.

1.2.

�3,4

��5

,�5�

Fin

d t

he

mag

nit

ud

e an

d d

irec

tion

of

RS�

for

the

give

n c

oord

inat

es.R

oun

d t

o th

en

eare

st t

enth

.

3.R

(2,�

3),S

(4,9

)4.

R(0

,2),

S(3

,12)

2�37�

�12

.2,8

0.5°

�10

9�

�10

.4,7

3.3°

5.R

(5,4

),S

(�3,

1)6.

R(1

,5),

S(�

4,�

6)

�73�

�8.

5,20

0.6°

�14

6�

�12

.1,2

45.6

°

Gra

ph

th

e im

age

of e

ach

fig

ure

un

der

a t

ran

slat

ion

by

the

give

n v

ecto

r(s)

.

7.�

AB

Cw

ith

ver

tice

s A

(�4,

3),B

(�1,

4),

8.tr

apez

oid

wit

h v

erti

ces

T(�

4,�

2),

C(�

1,1)

;t��

�4,�

3�R

(�1,

�2)

,S(�

2,�

3),Y

(�3,

�3)

;a��

�3,1

�an

d b�

��2

,4�

Fin

d t

he

mag

nit

ud

e an

d d

irec

tion

of

each

res

ult

ant

for

the

give

n v

ecto

rs.

9.y �

��7

,0�,

z��

�0,6

�10

.b��

�3,2

�,c�

���

2,3�

�85�

�9.

2,40

.6°

�26�

�5.

1,78

.7°

S�

Y�

T�

R�

SY

TR

x

y

O

C�

B�

A�

CB

A

x

y

O

x

y

O

B( –

2, 2

)

D( 3

, –3)

x

y

OC

( 1, –

1)

E( 4

, 3)

©G

lenc

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w-H

ill51

2G

lenc

oe G

eom

etry

Wri

te t

he

com

pon

ent

form

of

each

vec

tor.

1.2.

�6,4

��5

,�8�

Fin

d t

he

mag

nit

ud

e an

d d

irec

tion

of

FG�

for

the

give

n c

oord

inat

es.R

oun

d t

o th

en

eare

st t

enth

.

3.F

(�8,

�5)

,G(�

2,7)

4.F

(�4,

1),G

(5,�

6)

6�5�

�13

.4,6

3.4°

�13

0�

�11

.4,3

22.1

°

Gra

ph

th

e im

age

of e

ach

fig

ure

un

der

a t

ran

slat

ion

by

the

give

n v

ecto

r(s)

.

5.�

QR

Tw

ith

ver

tice

s Q

(�1,

1),R

(1,4

),6.

trap

ezoi

d w

ith

ver

tice

s J

(�4,

�1)

,T

(5,1

);s �

���

2,�

5�K

(0,�

1),L

(�1,

�3)

,M(�

2,�

3);c�

��5

,4�

and

d��

��2,

1�

Fin

d t

he

mag

nit

ud

e an

d d

irec

tion

of

each

res

ult

ant

for

the

give

n v

ecto

rs.

7.a�

���

6,4�

,b��

�4,6

�8.

e��

��4,

�5�

,f��

��1,

3�

2�26�

�10

.2,1

01.3

°�

29��

5.4,

201.

AV

IATI

ON

For

Exe

rcis

es 9

an

d 1

0,u

se t

he

foll

owin

g in

form

atio

n.

A je

t be

gins

a f

light

alo

ng a

pat

h du

e no

rth

at 3

00 m

iles

per

hour

.A w

ind

is b

low

ing

due

wes

tat

30

mile

s pe

r ho

ur.

9.F

ind

the

resu

ltan

t ve

loci

ty o

f th

e pl

ane.

abo

ut

301.

5 m

ph

10.F

ind

the

resu

ltan

t di

rect

ion

of

the

plan

e.ab

ou

t 5.

7°w

est

of

du

e n

ort

h

L�M

J�K

LM

JK

x

y

O

T�

R�

Q�

T

R

Qx

y

O

x

y

O

K( –

2, 4

)

L(3,

–4)

x

y

O

A( –

2, –

2)

B( 4

, 2)

Pra

ctic

e (

Ave

rag

e)

Vec

tors

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-6

9-6

Answers (Lesson 9-6)

© Glencoe/McGraw-Hill A19 Glencoe Geometry

An

swer

s

Readin

g t

o L

earn

Math

em

ati

csV

ecto

rs

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-6

9-6

©G

lenc

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cGra

w-H

ill51

3G

lenc

oe G

eom

etry

Lesson 9-6

Pre-

Act

ivit

yH

ow d

o ve

ctor

s h

elp

a p

ilot

pla

n a

fli

ght?

Rea

d th

e in

trod

uct

ion

to

Les

son

9-6

at

the

top

of p

age

498

in y

our

text

book

.

Wh

y do

pil

ots

ofte

n h

ead

thei

r pl

anes

in

a s

ligh

tly

diff

eren

t di

rect

ion

fro

mth

eir

dest

inat

ion

?S

amp

le a

nsw

er:

to c

om

pen

sate

fo

r th

e ef

fect

of

the

win

d s

o t

hat

th

e re

sult

will

be

that

th

e p

lan

e w

ill a

ctu

ally

fly

in t

he

corr

ect

dir

ecti

on

Rea

din

g t

he

Less

on

1.S

upp

ly t

he

mis

sin

g w

ords

or

phra

ses

to c

ompl

ete

the

foll

owin

g se

nte

nce

s.

a.A

is

a d

irec

ted

segm

ent

repr

esen

tin

g a

quan

tity

th

at h

as b

oth

mag

nit

ude

an

d di

rect

ion

.

b.

Th

e le

ngt

h o

f a

vect

or i

s ca

lled

its

.

c.T

wo

vect

ors

are

para

llel

if

and

only

if

they

hav

e th

e sa

me

or

dire

ctio

n.

d.

A v

ecto

r is

in

if

it

is d

raw

n w

ith

in

itia

l po

int

at t

he

orig

in.

e.T

wo

vect

ors

are

equ

al i

f an

d on

ly i

f th

ey h

ave

the

sam

e an

d th

e

sam

e.

f.T

he

sum

of

two

vect

ors

is c

alle

d th

e .

g.A

vec

tor

is w

ritt

en i

n

if i

t is

exp

ress

ed a

s an

ord

ered

pai

r.

h.

Th

e pr

oces

s of

mu

ltip

lyin

g a

vect

or b

y a

con

stan

t is

cal

led

.

2.W

rite

eac

h v

ecto

r de

scri

bed

belo

w i

n c

ompo

nen

t fo

rm.

a.a

vect

or i

n s

tan

dard

pos

itio

n w

ith

en

dpoi

nt

(a,b

)�a

,b�

b.

a ve

ctor

wit

h i

nit

ial

poin

t (a

,b)

and

endp

oin

t (c

,d)

�c�

a,d

�b

�c.

a ve

ctor

in

sta

nda

rd p

osit

ion

wit

h e

ndp

oin

t (�

3,5)

��3,

5�d

.a

vect

or w

ith

in

itia

l po

int

(2,�

3) a

nd

endp

oin

t (6

,�8)

�4,�

5�e.

a��

b�if

a��

��3,

5�an

d b�

��6

,�4�

�3,1

�f.

5u�if

u��

�8,�

6��4

0,�

30�

g.�

�1 3� v�if

v��

��15

,24�

�5,�

8�h

.0.

5u��

1.5v�

if u�

��1

0,�

10�

and

v��

��8,

6���

7,4�

Hel

pin

g Y

ou

Rem

emb

er3.

A g

ood

way

to

rem

embe

r a

new

mat

hem

atic

al t

erm

is

to r

elat

e it

to

a te

rm y

ou a

lrea

dykn

ow.Y

ou le

arne

d ab

out

scal

e fa

ctor

sw

hen

you

stud

ied

sim

ilari

ty a

nd d

ilati

ons.

How

is t

heid

ea o

f a

scal

arre

late

d to

sca

le f

acto

rs?

Sam

ple

an

swer

:A s

cala

ris

th

e te

rm u

sed

for

a co

nst

ant

(a s

pec

ific

real

nu

mb

er)

wh

en w

ork

ing

with

vec

tors

.A v

ecto

rh

as b

oth

mag

nit

ud

e an

d d

irec

tio

n,w

hile

a s

cala

r is

just

a m

agn

itu

de.

Mu

ltip

lyin

g a

vec

tor

by a

po

siti

ve s

cala

r ch

ang

es t

he

mag

nit

ud

e o

f th

eve

cto

r,bu

t n

ot

the

dir

ecti

on

,so

it r

epre

sen

ts a

ch

ang

e in

sca

le.

scal

ar m

ult

iplic

atio

nco

mp

on

ent

formre

sult

ant

dir

ecti

on

mag

nit

ud

est

and

ard

po

siti

on

op

po

site

mag

nit

ud

e

vect

or

©G

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w-H

ill51

4G

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eom

etry

Rea

din

g M

ath

emat

ics

Man

y qu

anti

ties

in

nat

ure

can

be

thou

ght

of a

s ve

ctor

s.T

he

scie

nce

of

phys

ics

invo

lves

man

y ve

ctor

qu

anti

ties

.In

rea

din

g ab

out

appl

icat

ion

sof

mat

hem

atic

s,as

k yo

urs

elf

wh

eth

er t

he

quan

titi

es i

nvo

lve

only

mag

nit

ude

or

both

mag

nit

ude

an

d di

rect

ion

.Th

e fi

rst

kin

d of

qu

anti

tyis

cal

led

scal

ar.T

he

seco

nd

kin

d is

a v

ecto

r.

Cla

ssif

y ea

ch o

f th

e fo

llow

ing.

Wri

te s

cala

ror

vec

tor.

1.th

e m

ass

of a

boo

ksc

alar

2.a

car

trav

elin

g n

orth

at

55 m

phve

cto

r

3.a

ball

oon

ris

ing

24 f

eet

per

min

ute

vect

or

4.th

e si

ze o

f a

shoe

scal

ar

5.a

room

tem

pera

ture

of

22 d

egre

es C

elsi

us

scal

ar

6.a

wes

t w

ind

of 1

5 m

phve

cto

r

7.th

e ba

ttin

g av

erag

e of

a b

aseb

all

play

ersc

alar

8.a

car

trav

elin

g 60

mph

vect

or

9.a

rock

fal

lin

g at

10

mph

vect

or

10.y

our

age

scal

ar

11.t

he

forc

e of

Ear

th’s

gra

vity

act

ing

on a

mov

ing

sate

llit

eve

cto

r

12.t

he

area

of

a re

cord

rot

atin

g on

a t

urn

tabl

esc

alar

13.t

he

len

gth

of

a ve

ctor

in

th

e co

ordi

nat

e pl

ane

scal

ar

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-6

9-6

Answers (Lesson 9-6)

© Glencoe/McGraw-Hill A20 Glencoe Geometry

Stu

dy G

uid

e a

nd I

nte

rven

tion

Tran

sfo

rmat

ion

s w

ith

Mat

rice

s

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-7

9-7

©G

lenc

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w-H

ill51

5G

lenc

oe G

eom

etry

Lesson 9-7

Tran

slat

ion

s an

d D

ilati

on

sA

vec

tor

can

be

repr

esen

ted

by t

he

orde

red

pair

�x,

y�or

by t

he

colu

mn

mat

rix

.Wh

en t

he

orde

red

pair

s fo

r al

l th

e ve

rtic

es o

f a

poly

gon

are

plac

ed t

oget

her

,th

e re

sult

ing

mat

rix

is c

alle

d th

e ve

rtex

mat

rix

for

the

poly

gon

.

For

�A

BC

wit

h A

(�2,

2),B

(2,1

),an

d C

(�1,

�1)

,th

e ve

rtex

mat

rix

for

the

tria

ngl

e is

.

For

�A

BC

abov

e,u

se a

mat

rix

to f

ind

th

e co

ord

inat

es o

f th

eve

rtic

es o

f th

e im

age

of �

AB

Cu

nd

er t

he

tran

slat

ion

(x,

y) →

(x�

3,y

�1)

.T

o tr

ansl

ate

the

figu

re 3

un

its

to t

he

righ

t,ad

d 3

to e

ach

x-c

oord

inat

e.T

o tr

ansl

ate

the

figu

re 1

un

it d

own

,add

�1

to e

ach

y-c

oord

inat

e.V

erte

x M

atri

xT

ran

slat

ion

V

erte

x M

atri

xof

�A

BC

Mat

rix

of �

A�B

�C�

��

Th

e co

ordi

nat

es a

re A

�(1,

1),B

�(5,

0),a

nd

C�(

2,�

2).

For

�A

BC

abov

e,u

se a

mat

rix

to f

ind

th

e co

ord

inat

es o

f th

e ve

rtic

esof

th

e im

age

of �

AB

Cfo

r a

dil

atio

n c

ente

red

at

the

orig

in w

ith

sca

le f

acto

r 3.

Sca

leV

erte

x M

atri

xV

erte

x M

atri

xFa

ctor

of �

AB

Cof

�A

�B�C

3

Th

e co

ordi

nat

es a

re A

�(�

6,6)

,B�(

6,3)

,an

d C

�(�

3,�

3).

Use

a m

atri

x to

fin

d t

he

coor

din

ates

of

the

vert

ices

of

the

imag

e of

eac

h f

igu

reu

nd

er t

he

give

n t

ran

slat

ion

s or

dil

atio

ns.

1.�

AB

Cw

ith

A(3

,1),

B(�

2,4)

,C(�

2,�

1);(

x,y)

→(x

�1,

y�

2)A

�(2,

3),B

�(�

3,6)

,C�(

�3,

1)2.

para

llel

ogra

m R

ST

Uw

ith

R(�

4,�

2),S

(�3,

1),T

(3,4

),U

(2,1

);(x

,y)

→(x

�4,

y�

3)

R�(

�8,

�5)

,S�(

�7,

�2)

,T�(

�1,

1),U

�(�

2,�

2)3.

rect

angl

e P

QR

Sw

ith

P(4

,0),

Q(3

,�3)

,R(�

3,�

1),S

(�2,

2);(

x,y)

→(x

�2,

y�

1)P

�(2,

1),Q

�(1,

�2)

,R�(

�5,

0),S

�(�

4,3)

4.�

AB

Cw

ith

A(�

2,�

1),B

(�2,

�3)

,C(2

,�1)

;dil

atio

n c

ente

red

at t

he

orig

in w

ith

sca

lefa

ctor

2A

�(�

4,�

2),B

�(�

4,�

6),C

�(4,

�2)

5.pa

rall

elog

ram

RS

TU

wit

h R

(4,�

2),S

(�4,

�1)

,T(�

2,3)

,U(6

,2);

dila

tion

cen

tere

d at

th

eor

igin

wit

h s

cale

fac

tor

1.5

R�(

6,�

3),S

�(�

6,�

1.5)

,T�(

�3,

4.5)

,U�(

9,3)

�6

6�

3

63

�3

�2

2�

1

21

�1

15

2 1

0�

2

33

3 �

1�

1�

1�

22

�1

2

1�

1

�2

2�

1

21

�1

x

y

B( 2

, 1)

C( –

1, –

1)

A( –

2, 2

)

x

y

Exer

cises

Exer

cises

Exam

ple1

Exam

ple1

Exam

ple2

Exam

ple2

©G

lenc

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w-H

ill51

6G

lenc

oe G

eom

etry

Ref

lect

ion

s an

d R

ota

tio

ns

Wh

en y

ou r

efle

ct a

n i

mag

e,on

e w

ay t

o fi

nd

the

coor

din

ates

of

the

refl

ecte

d ve

rtic

es i

s to

mu

ltip

ly t

he

vert

ex m

atri

x of

th

e ob

ject

by

are

flec

tion

mat

rix.

To

perf

orm

mor

e th

an o

ne

refl

ecti

on,m

ult

iply

by

one

refl

ecti

on m

atri

xto

fin

d th

e fi

rst

imag

e.T

hen

mu

ltip

ly b

y th

e se

con

d m

atri

x to

fin

d th

e fi

nal

im

age.

Th

em

atri

ces

for

refl

ecti

ons

in t

he

axes

,th

e or

igin

,an

d th

e li

ne

y�

xar

e sh

own

bel

ow.

Fo

r a

refl

ecti

on

in t

he:

x-ax

isy-

axis

ori

gin

line

y�

x

Mu

ltip

ly t

he

vert

ex

mat

rix

by:

�A

BC

has

ver

tice

s A

(�2,

3),B

(1,4

),an

d

C(3

,0).

Use

a m

atri

x to

fin

d t

he

coor

din

ates

of

the

vert

ices

of

th

e im

age

of �

AB

Caf

ter

a re

flec

tion

in

th

e x-

axis

.T

o re

flec

t in

th

e x-

axis

,mu

ltip

ly t

he

vert

ex m

atri

x of

�A

BC

by t

he

refl

ecti

on m

atri

x fo

r th

e x-

axis

.

Ref

lect

ion

Mat

rix

Ver

tex

Mat

rix

Ver

tex

Mat

rix

for

x-ax

isof

�A

BC

of �

A’B

’C’

Use

a m

atri

x to

fin

d t

he

coor

din

ates

of

the

vert

ices

of

the

imag

e of

eac

h f

igu

reu

nd

er t

he

give

n r

efle

ctio

n.

1.�

AB

Cw

ith

A(�

3,2)

,B(�

1,3)

,C(1

,0);

refl

ecti

on i

n t

he

x-ax

is

A�(

�3,

�2)

,B�(

�1,

�3)

,C�(

1,0)

2.�

XY

Zw

ith

X(2

,�1)

,Y(4

,�3)

,Z(�

2,1)

;ref

lect

ion

in

th

e y-

axis

X�(

�2,

�1)

,Y�(

�4,

�3)

,Z�(

2,1)

3.�

AB

Cw

ith

A(3

,4),

B(�

1,0)

,C(�

2,4)

;ref

lect

ion

in

th

e or

igin

A�(

�3,

�4)

,B�(

1,0)

,C�(

2,�

4)

4.pa

rall

elog

ram

RS

TU

wit

h R

(�3,

2),S

(3,2

),T

(5,�

1),U

(�1,

�1)

;ref

lect

ion

in t

he li

ne y

�x

R�(

2,�

3),S

�(2,

3),T

�(�

1,5)

,U�(

�1,

�1)

5.�

AB

Cw

ith

A(2

,3),

B(�

1,2)

,C(1

,�1)

;ref

lect

ion

in

th

e or

igin

,th

en r

efle

ctio

n i

n t

he

lin

ey

�x

A�(

�3,

�2)

,B�(

�2,

1),C

�(1,

�1)

6.pa

rall

elog

ram

RS

TU

wit

h R

(0,2

),S

(4,2

),T

(3,�

2),U

(�1,

�2)

;ref

lect

ion

in

th

e x-

axis

,th

en r

efle

ctio

n i

n t

he

y-ax

is

R�(

0,�

2),S

�(�

4,�

2),T

�(�

3,2)

,U�(

1,2)

�2

13

�3

�4

0�

21

3

34

01

0 0

�1

x

y

A�

B�

AB

C

01

10

�1

0

0�

1�

10

0

11

00

�1

Stu

dy G

uid

e a

nd I

nte

rven

tion

(con

tinued

)

Tran

sfo

rmat

ion

s w

ith

Mat

rice

s

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-7

9-7

Exam

ple

Exam

ple

Exer

cises

Exer

cises

Answers (Lesson 9-7)

© Glencoe/McGraw-Hill A22 Glencoe Geometry

Readin

g t

o L

earn

Math

em

ati

csTr

ansf

orm

atio

ns

wit

h M

atri

ces

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-7

9-7

©G

lenc

oe/M

cGra

w-H

ill51

9G

lenc

oe G

eom

etry

Lesson 9-7

Pre-

Act

ivit

yH

ow c

an m

atri

ces

be

use

d t

o m

ake

mov

ies?

Rea

d th

e in

trod

uct

ion

to

Les

son

9-7

at

the

top

of p

age

506

in y

our

text

book

.

•W

hat

kin

d of

tra

nsf

orm

atio

n s

hou

ld b

e u

sed

to m

ove

a po

lygo

n?

refl

ecti

on

,tra

nsl

atio

n,o

r ro

tati

on

•W

hat

kind

of

tran

sfor

mat

ion

shou

ld b

e us

ed t

o re

size

a p

olyg

on?

dila

tio

n

Rea

din

g t

he

Less

on

1.W

rite

a v

erte

x m

atri

x fo

r ea

ch f

igu

re.

a.�

AB

Cb

.par

alle

logr

am A

BC

D

2.M

atch

eac

h t

ran

sfor

mat

ion

fro

m t

he

firs

t co

lum

n w

ith

th

e co

rres

pon

din

g m

atri

x fr

omth

e se

con

d or

th

ird

colu

mn

.In

eac

h c

ase,

the

vert

ex m

atri

x fo

r th

e pr

eim

age

of a

fig

ure

is m

ult

ipli

ed o

n t

he

left

by

one

of t

he

mat

rice

s be

low

to

obta

in t

he

imag

e of

th

e fi

gure

.A

ll r

otat

ion

s li

sted

are

cou

nte

rclo

ckw

ise

thro

ugh

th

e or

igin

.(S

ome

mat

rice

s m

ay b

e u

sed

mor

e th

an o

nce

or

not

at

all.)

a.re

flec

tion

ove

r th

e y-

axis

vii.

v.b

.90

°ro

tati

onvi

iic.

refl

ecti

on o

ver

the

lin

e y

�x

iiiii

.vi

.d

.27

0°ro

tati

onv

e.re

flec

tion

ove

r th

e or

igin

iiii

i.vi

i.f.

180°

rota

tion

iig.

refl

ecti

on o

ver

the

x-ax

isvi

iiv

.vi

ii.

h.

360°

rota

tion

i

Hel

pin

g Y

ou

Rem

emb

er3.

How

can

you

rem

embe

r or

qu

ickl

y fi

gure

ou

t th

e m

atri

ces

for

the

tran

sfor

mat

ion

s in

Exe

rcis

e 2?

Vis

ual

ize

or

sket

ch h

ow t

he

“un

it p

oin

ts”

(1,0

) o

n t

he

x-ax

is a

nd

(0,1

) o

n t

he

y-ax

is a

re m

oved

by

the

tran

sfo

rmat

ion

.Wri

te t

he

ord

ered

pai

rfo

r th

e im

age

po

ints

in a

2 �

2 m

atri

x,w

ith t

he

coo

rdin

ates

of

the

imag

e o

fth

e x-

axis

un

it p

oin

t in

th

e fir

st c

olu

mn

an

d t

he

coo

rdin

ates

of

the

imag

e o

fth

e y-

axis

un

it p

oin

t in

th

e se

con

d c

olu

mn

.

0�

1 1

0

0�

1 �

10

10

0�

10

1 1

0

�1

0

01

�1

0

0�

1

0

1 �

10

10

01

�4

�1

41

0

33

03

�3

�1

1

4�

4

BC

AD

x

y

O

B

C

A

x

y

O

©G

lenc

oe/M

cGra

w-H

ill52

0G

lenc

oe G

eom

etry

Vec

tor

Add

itio

nV

ecto

rs a

re p

hys

ical

qu

anti

ties

wit

h m

agn

itu

de a

nd

dire

ctio

n.F

orce

an

d ve

loci

ty a

re t

wo

exam

ples

.We

wil

l in

vest

igat

e ad

din

g ve

ctor

qu

anti

ties

.Th

e su

m o

f tw

o ve

ctor

s is

cal

led

are

sult

ant

vect

oror

just

th

e re

sult

ant.

Tw

o se

par

ate

forc

es,o

ne

mea

suri

ng

20 u

nit

s an

d t

he

oth

er m

easu

rin

g 40

un

its,

act

on a

n

obje

ct.I

f th

e an

gle

bet

wee

n t

he

forc

es i

s 50

°,fi

nd

th

em

agn

itu

de

and

dir

ecti

on o

f th

e re

sult

ant

forc

e.

Fir

st,t

he

vect

ors

mu

st b

e re

arra

nge

d by

pla

cin

g th

e ta

il o

f th

e 20

-un

it v

ecto

r at

th

e h

ead

of t

he

40-u

nit

vec

tor.

Sin

ce t

hes

e ve

ctor

s ar

e n

ot p

erpe

ndi

cula

r,th

e h

oriz

onta

l an

d ve

rtic

alco

mpo

nen

ts o

f on

e of

th

e ve

ctor

s m

ust

be

fou

nd.

Usi

ng

trig

onom

etry

,th

e h

oriz

onta

l co

mpo

nen

t m

ust

be

(20

cos

50°)

u

nit

s an

d th

e ve

rtic

al c

ompo

nen

t m

ust

be

(20

sin

50°

) u

nit

s.R

epla

cin

g th

e 20

-un

it v

ecto

r w

ith

th

ese

com

pon

ents

,we

can

n

ow f

orm

tw

o ve

ctor

s pe

rpen

dicu

lar

and

use

th

e P

yth

agor

ean

T

heo

rem

to

fin

d th

e re

sult

ant.

r2�

(40

�20

cos

50°

)2�

(20

sin

50°

)2

r2�

(52.

9)2

�(1

5.3)

2

r2�

3032

.5r2

�55

.1

tan

O�� 40

2 �02s 0in

c5 os0°50

°�

�0.

2898

m�

O�

16

Th

eref

ore,

the

resu

ltan

t fo

rce

is 5

5.1

un

its

dire

cted

16°

from

th

e 40

-un

it f

orce

.

Sol

ve.R

oun

d a

ll a

ngl

e m

easu

res

to t

he

nea

rest

deg

ree.

Rou

nd

all

oth

er m

easu

res

to t

he

nea

rest

ten

th.

1.A

pla

ne

flie

s du

e w

est

at 2

50 k

ilom

eter

s pe

r h

our

wh

ile

the

win

d bl

ows

sou

th a

t 70

kilo

met

ers

per

hou

r.F

ind

the

plan

e’s

resu

ltan

t ve

loci

ty.

259.

6 km

/h,1

6�so

uth

of

wes

t

2.A

pla

ne

flie

s ea

st f

or 2

00 k

m,t

hen

60°

sou

th o

f ea

st f

or 8

0 km

.Fin

d th

e pl

ane’

s di

stan

cean

d di

rect

ion

fro

m i

ts s

tart

ing

poin

t.

249.

8 km

,16�

sou

th o

f ea

st

3.O

ne

forc

e of

100

un

its

acts

on

an

obj

ect.

An

oth

er f

orce

of

80 u

nit

s ac

ts o

n t

he

obje

ct a

t a

40°

angl

e fr

om t

he

firs

t fo

rce.

Fin

d th

e re

sult

ant

forc

e on

th

e ob

ject

.

169.

3 u

nit

s,18

�fr

om

th

e 10

0-u

nit

fo

rce

O

20

40 �

20

cos

50�

20 s

in 5

0�r

20

20 c

os 5

0�

20 s

in 5

0�

50�

O

20 u

nits

40 u

nits

50�

O

20 u

nits

40 u

nits

50�

En

rich

men

t

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

9-7

9-7

Exam

ple

Exam

ple

Answers (Lesson 9-7)