The figure is not drawn to scale. Triangle EFD is an isosceles triangle. Triangle BCD is an equilateral triangle. ∠FDE is
35 of ∠CBD and ∠CDF = ∠BDE.
- Find ∠CDF.
- Find ∠BED.
(a)
∠CDB = 60° (Equilateral triangle)
∠FDE
= ∠CDB x
35 = 60° x
35 = 36°
∠CDF = ∠BDE
∠CDF
= ∠CDB - ∠FDA) ÷ 2
= (60° - 36°) ÷ 2
= 24° ÷ 2
= 12° (Isosceles triangle)
(b)
∠BED
= 180° - ∠CBD - ∠CDF
= 180° - 60° - 12°
= 108° (Angles sum of triangle)
Answer(s): (a) 12°; (b) 108°