The figure is not drawn to scale. ABDE is a parallelogram. ∠EAO is 60° and ∠DBC is 28°. ABC is an isosceles triangle and AB = BC.
- Find ∠OCB.
- Find ∠AED.
(a)
∠BOA = 60° (Alternate angles, AE//BD)
∠BOC
= 180° - 60°
= 120° (Angles on a straight line)
∠OCB
= 180° - 120° - 28°
= 32° (Angles sum of triangle)
(b)
∠BAO = 32° (Isosceles triangle ABC)
∠AED
= 180° - 60° - 32°
= 88° (Interior angles, AB//ED)
Answer(s): (a) 32°; (b) 88°