Download 4-4 Notes

GEOMETRY
SECTION 4.4 NOTES – PROVING TRIANGLES CONGRUENT (ASA and AAS)
Learning Targets:
-Prove two triangles congruent using ASA
- Prove two triangles congruent using AAS
***Proof Hints***
Ways to prove triangles congruent
Angle – Side – Angle
If two angles and the included side of one triangle are congruent to two angles and the
included side of second triangle,
Then the two triangles are congruent.
B
D
A
C
E
1. Given: AD || EC , BD  BC
Prove: ABD  EBC
Reason
n
C
A
B
D
E
Angle – Angle – Side
If two angles and a non-included side of one triangle are congruent to two angles and
the corresponding non-included side of a second triangle,
Then the two triangles are congruent.
B
A
D
E
C
2. Given: B  C , D  F , M is the midpoint of DF
Prove: BDM  CFM
Statement
Reason
n
C
B
D
F
M
3. Given: AB  AD, DE  AD
ABC  DEC
E
A
C
B
Reason
n
BC  EC
Prove:
Statement
D