Lesson 2­Congruent Figures.notebook

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March 06, 2015

Congruent Figures

Two figures are congruent iff:all corresponding angles are congruentall corresponding sides are congruent

Example:

F

D

E

A   F AB   FDB   D BC   EDC   E AC   FE

*order counts*

Lesson 2­Congruent Figures.notebook

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March 06, 2015

F

D

E

Congruence Statement:

1. Start with the triangle on the LEFT or TOP.

2. Put the FIRST triangle in ALPHABETICAL order.

3. Put the SECOND triangle CORRESPONDING to the FIRST.

ΔABC   ΔFDEcongruence statement:

1)

2) 3)

Lesson 2­Congruent Figures.notebook

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March 06, 2015

congruence statement

List pairs of congruentcorresponding parts

Part 1

Part 2

Part 3

Find the value of x.

Find the value of y.

Lesson 2­Congruent Figures.notebook

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March 06, 2015

In the diagram, ABCD   KJHL.

1. Find the value of x.

2. Find the value of y.

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Latest News Bulletin:The most popular congruent figures are triangles!

Be sure to remember that in congruent figures, the corresponding parts are also congruent.

When two triangles are congruent, there are 6 facts that are true about the triangles:­there are 3 sets of congruent sides­there are 3 sets of congruent anglesNOTE: ­the corresponding congruent sides are marked with small line segments called hash marks­the corresponding congruent angles are marked with arcs

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Write a congruence statement for the triangles below. Identify all pairs of congruent corresponding parts.

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Third Angle Theorem:If 2 angles of 1 triangle are congruent to 2 angles of another triangle, then the third angles are congruent.

If and

then

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Find the value of x.

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Find the value of x.

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Can you conclude the triangles are congruent? How?

l l

ll ll

A

B C D

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Are these two triangles congruent? How do you know?

l

ll

lll

AB

C

DE

l

ll

lll

Lesson 2­Congruent Figures.notebook

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March 06, 2015

Classwork/Homework

Worksheet