In question a,
Interior angles are supplementary
So, x+50 = 180
x = 180-50
x = 130
Alternate angles are congruent
x = y = z
y = 130
Z = 130
In question b,
Alternate angles are congruent
y = 120
Interior angles are supplementary
So, y + 40 + z = 180
120 + 40 + z = 180
160 + z = 180
z = 180 - 160
z = 20
Alternate angles are congruent
z = x
x = 20
.... Hope this will help....
