TrapezoidsSec: 8.6

Sol: G.8 a, b, c

Foldable

* Fold over the fourth cut section and write Trapeziod on the outside.* Reopen the fold.

1. Opposite angles are congruent.

2. Consecutive angles are supplementary.

3. Opposite sides are congruent.

4. Diagonals bisect each other.

5. Diagonals make 2 congruent triangles.

1.Is a special type of parallelogram.

2. Has 4 right angles

3. Diagonals are congruent.

1. Is A Special type of Parallelogram

2. Has 4 Congruent sides

3. Diagonals are perpendicular.

4. Diagonals bisect opposite angles

1. Is a parallelogram, rectangle, and rhombus

2. 4 congruent sides and 4 congruent (right) angles

Foldable

* On the left hand section, draw a trapezoid.

1. Opposite angles are congruent.

2. Consecutive angles are supplementary.

3. Opposite sides are congruent.

4. Diagonals bisect each other.

5. Diagonals make 2 congruent triangles.

* On the right hand side, list all of the properties of a trapezoid.

1.Is a special type of parallelogram.

2. Has 4 right angles

3. Diagonals are congruent.

1. Is A Special type of Parallelogram

2. Has 4 Congruent sides

3. Diagonals are perpendicular.

4. Diagonals bisect opposite angles

1. Is a parallelogram, rectangle, and rhombus

2. 4 congruent sides and 4 congruent (right) angles

1. 1. Is a quadrilateral with exactly onepair of parallel sides.

2. There are two pairs of bases angles.

A trapezoid is a quadrilateral with exactly __________ pair of _____________________ sides.

Example:

The parallel sides are called _______________.The nonparallel sides are called ________________.In a trapezoid there are two pairs of

_________________ angles.

B

E

C

D

In a trapezoid, ONLY one pair of

opposite sides can be parallel. If

both pairs of opposite sides are

parallel, the quadrilateral is a

________parallelogram_____.

one

parallel

Bases

Legs

Base

Base

Base

Leg LegBase Angles

If the legs of a trapezoid are congruent, then the trapezoid is an _________ trapezoid.

Example:

Isosceles

RK

D O

According to the property

above, which two sides are

congruent?

________ and ________

Label the picture

appropriately.

Theorem 8.18 : Both pairs of base angles of an isosceles trapezoid are Congruent.

Theorem 8.19 : The diagonals of an isosceles trapezoid are Congruent.

RK

D OAccording to the property above,

which two pairs of angles are

congruent?

________ ________

________ ________

Label the picture appropriately.

RK

D O According to the property

above, which two segments

are congruent?

________ ________

The _________ of a trapezoid is the segment that joins the midpoints of its legs.

Theorem 8.20 : The median of a trapezoid is Parallel to the bases, and its measure is one-half the sum of the measures of the Bases.

Median

M R

E

CY

A

According to the statement above, if RM is the median,

which segments are congruent to each other?

________ ________

________ ________

A B

CD

EF

)(2

1DCABEF

Suggested Assignments:

Classwork: Handouts

Homework: pg 442 13-19 all 39