In the diagram, MNR is a tangent to the circle centre O at N and ∠NOS = 108°. Find ∠OSN
Attached Figure / Diagram
A
72°
B
32°
C
36°
D
18°
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
The sum of angles in a triangle = 180º
(180 - 108)º = 72º
Isosceles triangle has both two equal sides and two equal angles.
∠OSN = ∠SON = \(\frac{72}{2}\)
= 36º
Source: WAEC / JAMB / NECO Classroom Archive (Record #64837)