PSLEIn the figure, DEFG is a parallelogram. DBG and BFC are straight lines. ∠CFG = 153°, ∠DGF = 45° and ∠DFB = 21°.
- Find ∠EFC.
- Find ∠EDF.
(a)
∠EFG
= 180° - 45°
= 135° (Interior angles)
∠EFC
= 360° - 153° - 135°
= 72° (Angles at a point)
(b)
∠GFB
= 180° - 153°
= 27°(Angles on a straight line)
∠EDF
= ∠DFG
= 27° + 21°
= 48° (Alternate angles)
Answer(s): (a) 72°; (b) 48°