Do Now 4/3/13Do Now 4/3/13

Copy HW in your planner.Copy HW in your planner.– Text p. 338, #1-14, 19, 20, 22, 24, 25Text p. 338, #1-14, 19, 20, 22, 24, 25

NJASK Warm Up:NJASK Warm Up:

A rope 64 inches long is cut into three pieces. The A rope 64 inches long is cut into three pieces. The second piece is 4 inches longer than the first. The second piece is 4 inches longer than the first. The third piece is 6 inches longer than the first. How third piece is 6 inches longer than the first. How many inches long is each piece?many inches long is each piece?

ObjectiveObjective

SWBAT identify congruent figures and SWBAT identify congruent figures and use congruence to solve problems use congruence to solve problems

CongruentCongruentExactly the Exactly the same shapesame shape and and size.size.

Section 8.5, “Congruent Figures”Section 8.5, “Congruent Figures”

SimilarSimilarHaving theHaving the same shape same shape and and proportional side lengths. proportional side lengths.

Remember this???

Identify any congruent figures in the picture.

Identify if the figures are congruent, similar, or neither.

The sectors in the figure are congruent.

The sides of the octagons are not congruent. Each side of the outer figure is larger than each side of the inner figure. The figures are similar.

The sides of the figures are not congruent. The sides of the figures are not proportional therefore the figures are not similar.

Congruent TrianglesCongruent Triangles

CC

AA

BB

3.53.544

FF

DD

EE

3.53.5

22

44

DEFABC 22

Side-side-side ruleSide-side-side ruleFor triangles, if the corresponding sides are congruent, then the corresponding angles will always be congruent.

Congruent PolygonsCongruent PolygonsTwo polygons are congruent if their Two polygons are congruent if their angles and angles and sidessides have the same measures. have the same measures.

EFGHABCD

100100°°

8080°° 6060°°

CC

AA

DD

3.53.5 44

22

120120°°

BB

100100°°

8080°° 6060°°

GG

EE

HH

3.53.5 44

22

120120°°

FF

Try it outTry it outTell whether the figures are congruent.

Not congruent

Congruent, by the side-side-side rule.

Try it outTry it outTell whether the figures are congruent.

Not congruent. Sides are equal but angles are not equal.

Not congruent, angles are congruent but sides are not. The figures are similar.

Determine the unknown measure in the set of congruent polygons.

The unknown angle measure is 110°.

The corresponding parts of congruent polygons are congruent.

The unknown side length is 28 mm.

Determine the unknown measure in the set of congruent polygons.

Angle C is 60°.The corresponding parts of congruent polygons are congruent.

Side B is 9.

HomeworkHomework

– Text p. 338, #1-14, 19, 20, 22, 24, 25Text p. 338, #1-14, 19, 20, 22, 24, 25

NJASK7 PrepNJASK7 Prep