In the figure, G is the centre of the circle, DG is parallel to EF and ∠EGF = 108°. Find the values of
- ∠j
- ∠k
- ∠m
(a)
∠j
= (180° - 108°) ÷ 2
= 36° (Angle properties within a circle)
(b)
∠DGE = ∠j = 36° (Alternate angles)
∠k
= (180° - 36°) ÷ 2
= 72° (Angle properties within a circle)
(c)
∠m
= 360° - 108° - 36°
= 216° (Angles at a point)
Answer(s): (a) 36°; (b) 72°; (c) 216°