Pages 214 – 216 #10 – 26 (even), 36, and 37

10. 70.5, 70.5 12. 63 14. 5316. 32 18. 44 20. 5022. 40 24. 53 26. 10336. m 1 = 48m, m 2 = 60, m 3=7237. Najee; some of the measure of the

remote angle are equal to the measure of the interior angle.

Congruent Triangles

Chapter 4 Section 3

Learning Goal: Definition of Congruent Triangles, CPCTC

Never stop striving, never stop learning, never stop teaching.

What we know about Congruence

Segments

Angles

AC = 25 BD = 25A C B D

G H~=~=G 45°

H

45°

AC BD

~=~=

Congruent? Triangles

area = 16m2

area = 16m2

Congruent ?NO

Congruent ?NO

Congruent ?Yes

Congruent Triangles

Same SizeSame Shape

B. ARCHITECTURE A tower's roof is composed of congruent triangles all converging toward a point at the top. Name the congruent triangles.

Answer: ΔHIJ ΔKIL

Def. of Congruent Triangles

Congruence Statement?

A

B

C

E

D

F

∆ABC ∆DEF~=~=

CPCTC

A

B

C

E

D

F

∆ABC ∆DEF~=~=

What Parts are Corresponding?m A = m D

m B = m Em C = m F

AC DF~=~=

AB DE~=~=

BC EF~=~=

1

2

3

4

5

6

Naming Triangles

∆ABC ∆DEF~=~=

What Parts are Corresponding?m A = m D

m B = m Em C = m F

AC DF~=~=

AB DE~=~=

BC EF~=~=

1

2

3

4

5

6

You must make the

parts match the

name

CPCTC

∆ABC ∆DEF~=~=

m A = m Dm B = m Em C = m F

AC DF~=~=

AB DE~=~=

BC EF~=~=

1

2

3

4

5

6

The support beams on the fence form congruent triangles. Name the corresponding parts and triangle congruence statement if

CPCTC

,B E and A F

Properties of Triangle Congr.

X

Congruence Transformations

Rotation

Congruence Transformations

Translation (slide)

Congruence Transformations

Reflection (flip)

CPCTC

Name the Transformation that occurred if

BAC EFD Reflection and Translation

BAC FED Reflection

ACB EDF Rotation

Homework Pages 220 – 222; #6 – 9 (all), 10, 12,

14, 18, 19, 24, and 39 – 41 (all)(13 problems)