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.
Attached Figure / Diagram
A
67o
B
100o
C
113o
D
126o
E
134o
Verified Correct Answer: E.
Step-by-Step Mathematical Solution
From the diagram, < LMN = 180^\circ - (74^\circ + 39^\circ) (sum of angle in a triangle)
= 67^\circ
< LON = 2 x 67^\circ (angle subtended at the centre is twice the angle at the circumference)
= 134^\circ
Source: WAEC / JAMB / NECO Classroom Archive (Record #22196)