The figure, not drawn to scale, O is the centre of the circle and XC // YB // ZA. Find
- ∠WOZ
- ∠WBO
(a)
∠COY
= 180° - 98°
= 82° (Interior angles, XC//YO)
∠OZB = ∠OBZ = 31° (Isosceles triangle)
∠YOZ
= 31° + 31°
= 62° (Exterior angle of a triangle)
∠WOZ
= 82° + 62°
= 144°
(b)
∠BOZ
= 180° - 31° -31°
= 118° (Isosceles triangle)
∠WOB
= 360° - 144° - 118°
= 98° (Angles at a point)
WO = OB = Radius
∠WBO
= (180° - 98°) ÷ 2
= 82° ÷ 2
= 41° (Isosceles triangle)
Answer(s): (a) 144°; (b) 41°