PSLE ABCD is a rhombus. DFB and DECG are straight lines.
- Find ∠ABD.
- Find ∠DCG.
- Find ∠DFE.
(a)
∠ABD
= (180° - 104°) ÷ 2
= 38° (Isosceles triangle)
(b)
∠BCD
= ∠BAD
= 104° (Rhombus)
∠DCG
= 180° - 104°
= 76° (Angles on a straight line)
(c)
∠EBF
= ∠ABF
= 38° (Rhombus)
∠BEF
= 180° - 68°
= 112° (Angles on a straight line)
∠DFE
= 38° + 112°
= 150° (Exterior angle of a triangle)
Answer(s): (a) 38° (b) 76° (c) 150°