NEVER use SSA to prove triangles are

congruent!

CPCTCCorresponding Parts of Congruent Triangles are Congruent

SSS

Also, make flashcards for:

SAS, ASA, AAS, and HL

Lesson 4-4

• I can use triangle congruence postulates to prove that triangles are congruent

Given

Given TS ≅ TS∆RST ≅ ∆UTS Reflexive

SSS

Given

Given

US ≅ US∆RSU ≅ ∆TSU Reflexive SAS

∠RSU ≅ ∠TSU Def’n of angle bisector

Def’n of angle bisector

Given

Given

Given ∠ABD ≅ ∠CBD∆ABD ≅ ∆CBD ASA

Your turn!

Given

Given BD ≅ BD∆ABD ≅ ∆CBD Reflexive

SSS ∠A ≅ ∠C CPCTC

Given

Given DF ≅ DF∆EDF ≅ ∆GFD

Reflexive

AASCPCTC

∠EDF ≅ ∠GFD DG ≅ FE

AIA

Given

Given CB ≅ CB Reflexive ∆ABC ≅ ∆DBC HL ∠A ≅ ∠D CPCTC

∠ADB ≅ ∠CBD BD ≅ BD∆ABD ≅ ∆CDB

Given

Given

|| lines ↔ AIA ≅ Reflexive

SAS

∠DEG ≅ ∠FEG GE ≅ GE∆DEG ≅ ∆FEG DE ≅ FE

Given

GivenDef’n of angle bisector

Reflexive

ASACPCTC

Mickey Mouse

4-4 and 4-5

I got it!

I mostly get it

I need more helpI don’t get it at all!

#1 I can recognize SSS, SAS, ASA, AAS and HL postulates

#2 I can use triangle congruence postulates to prove that triangles are congruent #1

#1#2

ASSIGNMENT:4-4 worksheet