In this problem we have an isosceles trapezoid
that means
AB=CD
m
step 1
Find the value of x
msubstitute given values
x=56 degrees
step 2
Find the measure of z
Remember that
BC is parallel to AD
that means
x+z=180 -----> by consecutive interior angles
so
56+z=180
z=180-56
z=124 degrees
step 3
Find the measure of angle y
remember that
z=y -----> by an isosceles trapezoid
so
y=124 degrees