The figure, not drawn to scale, O is the centre of the circle and XC // YB // ZA. Find
- ∠WOZ
- ∠WBO
(a)
∠COY
= 180° - 94°
= 86° (Interior angles, XC//YO)
∠OZB = ∠OBZ = 28° (Isosceles triangle)
∠YOZ
= 28° + 28°
= 56° (Exterior angle of a triangle)
∠WOZ
= 86° + 56°
= 142°
(b)
∠BOZ
= 180° - 28° -28°
= 124° (Isosceles triangle)
∠WOB
= 360° - 142° - 124°
= 94° (Angles at a point)
WO = OB = Radius
∠WBO
= (180° - 94°) ÷ 2
= 86° ÷ 2
= 43° (Isosceles triangle)
Answer(s): (a) 142°; (b) 43°