In the figure, P is the centre of a semicircle and PKLM is a rhombus. Given that ∠PMN = 30°, find
- ∠r
- ∠s
(a)
∠PMN
= ∠PNM
= 30° (Isosceles triangle)
∠MPN
= 180° - 30° - 30°
= 120° (Angles sum of triangle)
∠r
= ∠MPN
= 120° (Corresponding angles)
(b)
∠s
= 180° - 120°
= 60° (Interior angles)
Answer(s): (a) 120°; (b) 60°