The figure, not drawn to scale, O is the centre of the circle and AF // BE // CD. Find
- ∠ZOC
- ∠ZEO
(a)
∠FOB
= 180° - 96°
= 84° (Interior angles, AF//BO)
∠OCE = ∠OEC = 29° (Isosceles triangle)
∠BOC
= 29° + 29°
= 58° (Exterior angle of a triangle)
∠ZOC
= 84° + 58°
= 142°
(b)
∠EOC
= 180° - 29° -29°
= 122° (Isosceles triangle)
∠ZOE
= 360° - 142° - 122°
= 96° (Angles at a point)
ZO = OE = Radius
∠ZEO
= (180° - 96°) ÷ 2
= 84° ÷ 2
= 42° (Isosceles triangle)
Answer(s): (a) 142°; (b) 42°