PSLE In the figure, BCGH is a parallelogram and DEFG is a rhombus. HGF is a straight line. ∠CBH = 56°, ∠GCD = 28° and ∠EDF = 32°.
- Find ∠CGD.
- Find ∠CDE.
(a)
∠CGH
= ∠CBH
= 56° (Parallelogram)
∠EFD
= ∠EDF
= 32° (Isosceles triangle)
∠DEF
= 180° - 32° - 32°
= 104° (Angles sum of triangle)
∠DGF
= ∠DEF
= 104° (Rhombus)
∠CGD
= 180° - 56° - 104°
= 20° (Angles on a straight line)
(b)
∠CDG
= 180° - 28° - 20°
= 132° (Angles sum of triangle)
∠FDG
= ∠EDF
= 32° (Rhombus)
∠CDE
= 360° - 132° - 32° - 32°
= 164° (Angles at a point)
Answer(s): (a) 20°; (b) 164°