4a) Why are the two triangles congruent? *
H
M
K
J
L
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Answer:
SAS Congruency (see below)
Step-by-step explanation:
First, prove the two triangles congruent:
You should know that ∠HKL ≅ ∠MKL because of Vertical Angles Congruence Theorem because they're vertical angles.
If it's already given that HK ≅ MK and JK ≅ LK, then you can clearly see that you can use the SAS Postulate to prove ΔHKL ≅ ΔMKL.
For a flow chart proof for this, refer to the image: