Let x = m∠3
Let y = m∠4
Because y is the supplement of x, therefore
x + y = 180° (1)
Because x is five times y, therefore
x = 5y (2)
Substitute (2) into (1).
5y + y = 180
6y = 180
y = 30°
From (2), obtain
x = 5*y = 5*30 = 150°
Answer:
m∠3 = 150°
m∠4 = 30°
