△WXY is a right triangle. Find the length of XY.

a.80mm
b.60
c.69.3
d.34.6

In the first triangle 80+20+p=180 (since sum of all angles of a triangle is 180)so p= 80also in second triangle 55+45+q=180 (since sum of all angles of a triangle is 180)so q=80so we can conclude that p=80 degrees q=80 degrees so p=q=80 degreeshence option b is correct

C. a,b, and d are not numbers. they are expressions.