PSLE CDEF is a trapezium with CD parallel to FE. CHD and GHF are straight lines and CG = GD. ∠GCF = 99°.
- Find ∠CFH.
- Find ∠DGH.
(a)
∠CFH
= 180° - 99° - 30°
= 51° (Angles sum of triangle)
(b)
∠CHF
= 69° (Alternate angles)
∠DCG
= 69° - 30°
= 39° (Exterior angle of a triangle)
∠DGH
= 180° - 39° - 39° - 30°
= 72° (Angles sum of triangle)
Answer(s): (a) 51°; (b) 72°