In the figure, E is the centre of a semicircle and EABC is a rhombus. Given that ∠ECD = 30°, find
- ∠y
- ∠z
(a)
∠ECD
= ∠EDC
= 30° (Isosceles triangle)
∠CED
= 180° - 30° - 30°
= 120° (Angles sum of triangle)
∠y
= ∠CED
= 120° (Corresponding angles)
(b)
∠z
= 180° - 120°
= 60° (Interior angles)
Answer(s): (a) 120°; (b) 60°