Question

Find the value of x and y
Angle A=x
Angle B=4y
Angle C=y
(Extended line) Angle D=5y
(Its a triangle)

Answer 1

SUM OF ALL ANGLE OF TRIANGLE 180°
so
x+4y+y=180°
x+5y=180°

now on extend at c
so
angle c+angle=180°. ( linear pair)180°
y+5y=180°
6y=180°
y=30°
x=180°-(5×30°)
x=180°-150°
x=30°