What Does this mean?

CPCTCCorresponding Partsof Congruent Triangles are Congruent

It means that once you know that 2 triangles are congruent, you know that ALL corresponding sides and angles are congruent

CPCTCCorresponding Partsof Congruent Triangles are Congruent

First, we need to know which sides and angles correspond!

1. Given that ∆ABC ∆DEF. List all of the corresponding sides and angles.

Sides

AB DE

BC EF

AC DF

Angles

LCAB LFDE

LABC LDEF

LBCA LEFD

• You practice with # 2 and #3 independently• When you finish complete the FIRST proof on

the 2nd page

Given: DG DE and FD DH a. Mark the diagram to reflect the given statements.

Take MENTAL NOTE: FE and HG are Corresponding Parts

Statement Reason

DG DE Given

FD DH Given L FDE L HDG Definition of

vertical angles

Prove: FE HG

∆ FDE ∆ HDG SAS

FE HG CPCTC

Now that we know ∆ FDE ∆ HDG we can use CPCTC

Statement Reason

Given: CQ WQ and HC HW Prove: L CHQ LWHQ

a. Mark the diagram to reflect all congruencies, then complete the proof

Take MENTAL NOTE: L CHQ and LWHQ are Corresponding Parts

CQ WQ Given

HC HW Given

HQ HQ Same segment (reflexive Property)

∆ CDQ ∆ WHQ SSS

L CHQ L WHQ

Now that we know ∆ CHQ ∆ WHQ we can use CPCTC

CPCTC

HINT!!! To start the problem...you are going to need to draw an EXTRA line PY to create 2 triangles!!