Answer:
You could prove that ΔAMC and ΔBMD are congruent by AAS
Explanation:
Step 1: Given
step 2: Vertical Angles Thm (the two triangles connect at a point)
Step 3: AAS (This is because segment AC is congruent to segment BD, Angle A is congruent to angle B, and ∠AMC is congruent to ∠BMD making the triangles congruent by Angle angle side.
Step 4: CPCTC
Hope I helped! And plus... LA is not a Congruence theorem and It would not be HL because there is only one congruent side given.