2020 · Q81
A circle is inscribed in a triangle ABC. It touches the sides AB and AC at M and N respectively. If O is the centre of the circle and ∠A = 70°, then what is ∠MON equal to?
Elementary MathematicsCircles
- A90°
- B100°
- C110°
- D120°
Explanation
In quadrilateral AMON, angle MON = 360-90-90-70 = 110 degrees. Hence option (C). The two tangents from A make AMON kite-like with right angles at M and N.