PSLE ABCD and BDEF are rhombuses. CGD is a straight line.
- Find ∠DBG.
- Find ∠CDE.
(a)
∠BDC
= (180° - 110°) ÷2
= 70° ÷ 2
= 35° (Isosceles triangle)
∠DBG
= 180° - 121° - 35°
= 24° (Angles sum of triangle)
(b)
∠BFE
= 360° - 297°
= 63° (Angles at a point)
∠BDE = ∠BFE = 63° (Rhombus)
∠CDE
= 63° - 35°
= 28°
Answer(s): (a) 24°; (b) 28°