The figure, not drawn to scale, O is the centre of the circle and SX // TW // UV. Find
- ∠ROU
- ∠RWO
(a)
∠XOT
= 180° - 100°
= 80° (Interior angles, SX//TO)
∠OUW = ∠OWU = 29° (Isosceles triangle)
∠TOU
= 29° + 29°
= 58° (Exterior angle of a triangle)
∠ROU
= 80° + 58°
= 138°
(b)
∠WOU
= 180° - 29° -29°
= 122° (Isosceles triangle)
∠ROW
= 360° - 138° - 122°
= 100° (Angles at a point)
RO = OW = Radius
∠RWO
= (180° - 100°) ÷ 2
= 80° ÷ 2
= 40° (Isosceles triangle)
Answer(s): (a) 138°; (b) 40°