WAEC - Mathematics (1988 - No. 33)
In the diagram above, O is the centre of the circle through points L, M and N, if ∠MLN = 74o and ∠MNL = 39o, calculate ∠LON.
67o
100o
113o
126o
134o
설명
From the diagram, < LMN = 180° - (74° + 39°) (sum of angle in a triangle)
= 67°
< LON = 2 x 67° (angle subtended at the centre is twice the angle at the circumference)
= 134°