Answer:
Corresponding Parts of Congruent Triangles are Congruent.
ASA
Explanation:
We know that <YPC and angle <YPX are congruent angles. They are both 90°.
Side YP is congruent to YP, so these sides are congruent in both triangles.
<XYP and <YPZ are congruent, because the perpendicular bisector cuts <XYZ in two equal parts.
ASA (Angle, Side, Angle)