Page 92 - Math Course 3 (Book 2)

ASA and AAS Postulates

Your Turn!

Triangle Congruence Proof

Fill in the blank in the following paragraph proof.
B C
Given: AB || CD, AD || CB
Prove: △ABD ≅ △CDB
Proof: ∠ABD ≅ ∠CDB because alternate interi-
or are congruent when line are parallel.
∠ABD ≅ ∠CDB because alternate interior
are congruent. BD ≅ DB by Reflexive
Property △ABD ≅ △CDB by_______. A D

A. SSS B. SAS
C. ASA D. AAS Answer

Use AAS in Proofs Determine if Triangles Are Congruent

Complete the following flow proof. The curtain decorating the window forms 2
triangles at the top. B is the midpoint of AC.
Given: ∠ADB ≅ ∠ACE AE = 13 inches and CD = 13 inches. BE and BD
EC ≅ BD each use the same amount of material, 17 inches.
Prove: ∠AEC ≅ ∠ABD Which method would you use to prove
ΔABE ≅ ΔCBD?
Proof:
A. SSS
∠ADB ≅ ∠ACE EC ≅ BD ∠A ≅ ∠A B. SAS
Given Given Reflexive Property C. ASA
D. AAS

△AEC ≅ △ABD
A B C
???

∠AEC ≅ ∠ABD

CPCTC

A. SSS B. SAS
C. ASA D. AAS E D

Answer

Answer

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