Step-by-step explanation:
y=ax
70=a(140)
a = 70/140 = 1/2
y= x/2
y=45/2 = 22.5
The two blue angles are equal and two yellow angle are equal because of equal sides.
140 + blue angle = 180 ( linear pair )
hence, blue angle = 40
now, the sum of two yellow angles is 40 because of ext angle property.
hence, x + x = 40
2x=40
x = 20
