The figure, not drawn to scale, is made up of an isosceles triangle and a rhombus. ∠i = ∠j, ∠g is thrice ∠j, ∠h is twice ∠k and ∠i is less than ∠k by 36°.
- Find ∠i.
- Find the difference between ∠g and ∠i.
(a)
∠i = 1 u
∠j = 1 u
∠k = 1 u + 36°
1 u + 36° + 1 u + 36° + 1 u = 180° (Angles sum of triangle)
3 u + 72° = 180°
3 u = 180° - 72° = 108°
1 u = 108° ÷ 3 = 36°
∠i = 1 u = 36°
(b)
∠g = 3 u
∠g - ∠i
= 3 u - 1 u
= 2 u
= 2 x 36°
= 72°
Answer(s): (a) 36°; (b) 72°