Geometry/Trig 2 Name __________________________4-1 CPCTC Date ___________________________

Definition of Congruent: _________________________________________________________________________________________________________________________

Definition of Congruent Triangles: ________________________________________________________________________________________________________________________________________________________________________________________

Recall: ______________________________________________________________________________________________________________________________________

Write the converse to the above definition of Congruent TrianglesConverse: ____________________________________________________________________________________________________________________________________

From this definition of congruent triangles, we can determine that ________________________________________________________________________________________

Or _____________

So if you know triangles are congruent, ______________________________________________________________________________________________________________

Your justification (or reason) would be _____________ .

Example 1: When describing congruent polygons, vertices are listed in order of correspondence.

Examples: The figures are congruent. Write two statements that describe the congruence.

A

B

C X

Y

Z

ABC XYZ

CBA _____

BCA _____ACB _____

ABC _____

BAC _____

FGH _____

HFG _____

2) 3)

Diagram: Diagram:

Example 5: Suppose WXY ABF. Complete.

Example 6: The triangles shown are congruent. Complete.

Example 7: Suppose you know that AXB RST.

1) ABD _____ 2) AB ____

3) DC ____ 4) ABD _____

5) Which property allows you to conclude that BD BD?

1) W ____

5) F ____

2) mB ____

3) XY ____ 4) AF ____

6) WX ____

7) YWX _____ 8) BFA _____

Name the three pairs of corresponding sides.

Name the three pairs of corresponding angles.

Is it correct to say XAB STR?

Is it correct to say BXA TSR?

Example 4: If LMN RST, then the following corresponding parts are congruent.

Angles: Sides:

L _____

M _____

N _____

LM _____

MN _____

LN _____

Diagram:

Diagram:

Diagram:

Geometry/Trig 2 4-1 CPCTC Notes Page 2