It is given that AB∥CD and EF is a transversal
from the fiture we know that ∠AEF and∠EFG are alternate angles
so we get
∠AEF=∠EFG=75o
∠EFG=y=75o
from the figure we know that ∠EFC and ∠EFG form a linear pair of angles
so we get
∠EFC+∠EFG=180o
it can also be written as
x+y=180o
by substituting the value of y we get
x+75o=180o
x=105o
from the figure based on the exterior angle property it can be written as
∠EGD=∠EFG+∠FEG
by substituting the values in the above equation we get
125o=y+z
125o=75o+z
z=50o
therefore the values of x,y,z are 105o,75o,50o