In the figure, S is the centre of the circle, PS is parallel to QR and ∠QSR = 100°. Find the values of
- ∠w
- ∠x
- ∠y
(a)
∠w
= (180° - 100°) ÷ 2
= 40° (Angle properties within a circle)
(b)
∠PSQ = ∠w = 40° (Alternate angles)
∠x
= (180° - 40°) ÷ 2
= 70° (Angle properties within a circle)
(c)
∠y
= 360° - 100° - 40°
= 220° (Angles at a point)
Answer(s): (a) 40°; (b) 70°; (c) 220°