WAEC - Mathematics (2005 - No. 17)

In the diagram PQ and MN are straight lines. Find the value of x

13^o

17^o

28^o

30^o

The straight line MN = 180 = 2(x+30^o) + 86^o =>
180 = 2x + 60^o + 86^o => 180^o = 2x + 146^o => 2x = 180 - 46 = 34^o => x = 34/2 = 17^o