Unit 3: Support Proofs (1)

∆ABC≅∆XYZ
which is true?

• AB ≅ XY

• AB ≅ YX

• AB ≅ XZ

• BC ≅ CZ

If ∆LMK ≅ ∆LMT, then
∠K ≅ ____

• ∠T
• ∠M
• ∠L

If these triangles are congruent, state how you know.​ (a)  

• SSS Congruence
• SAS Congruence
• AAS Congruence
• HL Congruence
• Not necessarily congruent
• ASA Congruence

State if the two triangles are congruent.  If they are, state how you know.

• A
• B
• C
• D

Name the postulate, if possible, that makes the triangles congruent. (a)  

• SAS
• ASA
• AAS
• Not Possible
• SSS
• HL

(a)  

• Congruent by HL
• Congruent by SAS
• Congruent by SSS
• Not necessarily congruent
• Congruent by AAS
• Congruent by ASA

Which triangle congruence theorem (if any) can be used to prove the triangles are congruent? (a)  

• SSS
• ASA
• AAS
• SAS
• HL
• Not necessarily congruent

What is always the 1st thing you put into a proof?

Answer explanation

A given always comes first!

What is reason #4?

• Reflexive Property

• Definition of Midpoint

• Vertical angles are congruent.

• Given

Answer explanation

The reflexive theorem says that any part that is shared by both triangles is congruent to itself.

What is reason #3?

• SAS

• ASA

• SSS

• AAS

Answer explanation

There are two sets of congruent sides and one set of congruent angles, and the angle IS in the correct place for SAS!