Please help, prove how angle E and angle R are congruent

Answer:
.
Step-by-step explanation:
In ΔEMR and ΔNMR
MN ≅ MA Given
∠EMR ≅∠NMR Reflexive property
ME ≅ MR Given
ΔEMR ≅ ΔNMR S A S congruent - side Angle side
∠E ≅ ∠R Corresponding Part of Congruent Triangles