Answer:
A. Angle Y is a right angle.
B. The measure of angle Z is 45°.
E. The perpendicular bisector of creates two smaller isosceles triangles.
Explanation:
Let x represent the measures of base angles X and Z. 2x is the measure of vertex angle Y.
x + x + 2x = 180°
x = 45°
2x = m∠Y = 90°
The triangle is an isosceles right triangle which has base angles of 45°.
The perpendicular bisector of line XZ creates two smaller isosceles triangles with acute angles of 45°