JAMB - Mathematics (2008 - No. 22)
In the diagram above, PQ//RS. The size of the angle marked x is?
100o
80o
50o
30o
Explanation
Exterior angle = sum of two interior opposite angles
y = 50° (vert. opp ∠s are equal)
X = y + 30
X = 50 + 30
X = 80°
y = 50° (vert. opp ∠s are equal)
X = y + 30
X = 50 + 30
X = 80°