In the figure, EF is a straight line. ∠DGE = 90°, ∠HGJ is equal to ∠JGF but 30° more than ∠DGH.
- What line is perpendicular to EF?
- Find ∠HGJ.
(a)
Line DG or GD is perpendicular to EF
(b)
∠HGJ = ∠JGF = 1 u
∠DGH = 1 u - 30°
1 u + 1 u + 1 u - 30° = 90° (Right angle)
3 u = 90° + 30° = 120°
1 u = 120° ÷ 3 = 40°
Answer(s): (a) DG or GD; (b) 40°