Answer:
Step-by-step explanation:
I can't make specific statements about the proof because the midpoint is missing.
Givens
There are two right angles created by where the perpendicular bisector meats MN. Both are 90 degrees.
MN is bisected by the point on MN where the perpendicular meets MN
The Perpendicular Bisector is is common to both triangles.
Therefore the two triangles are congruent by SAS
PM = PN Parts contained in Congruent triangles are congruent.
