PSLE ABCD and BDEF are rhombuses. CGD is a straight line.
- Find ∠DBG.
- Find ∠CDE.
(a)
∠BDC
= (180° - 98°) ÷2
= 82° ÷ 2
= 41° (Isosceles triangle)
∠DBG
= 180° - 125° - 41°
= 14° (Angles sum of triangle)
(b)
∠BFE
= 360° - 285°
= 75° (Angles at a point)
∠BDE = ∠BFE = 75° (Rhombus)
∠CDE
= 75° - 41°
= 34°
Answer(s): (a) 14°; (b) 34°