Linear equation 8

Solution : 

Let the angle measure x

Supplement of x = 180^o - x

Difference between the angles = 30^o

180^o- x - x = 30^o

180^o- 2x = 30^o

180^o- 30^o = 2x

2x = 150^o

x = 150^o / 2 = 75^o

Therefore, x = 75^o

Supplement of x = 180^o-x = 180^o- 75^o = 105^o