PSLE In the figure, ABFG is a parallelogram and CDEF is a rhombus. GFE is a straight line. ∠BAG = 57°, ∠FBC = 26° and ∠DCE = 33°.
- Find ∠BFC.
- Find ∠BCD.
(a)
∠BFG
= ∠BAG
= 57° (Parallelogram)
∠DEC
= ∠DCE
= 33° (Isosceles triangle)
∠CDE
= 180° - 33° - 33°
= 103° (Angles sum of triangle)
∠CFE
= ∠CDE
= 103° (Rhombus)
∠BFC
= 180° - 57° - 103°
= 20° (Angles on a straight line)
(b)
∠BCF
= 180° - 26° - 20°
= 134° (Angles sum of triangle)
∠ECF
= ∠DCE
= 33° (Rhombus)
∠BCD
= 360° - 134° - 33° - 33°
= 160° (Angles at a point)
Answer(s): (a) 20°; (b) 160°