PSLE In the figure, ABD and FED are straight lines and EB is parallel to DC. ∠EFA is a right angle, ∠FAB = 54°, ∠ABC = 120° and ∠DEB = 66°.
- Find ∠ABE.
- Find ∠BCD.
(a)
∠ADF
= 180° - 90° - 54°
= 36° (Angles sum of triangle)
∠DBE
= 180° - 66° - 36°
= 78° (Angles sum of triangle)
∠ABE
= 180° - 78°
= 120° (Angles on a straight line)
(b)
∠DBC
= 360° - 120° - 78° - 120°
= 42° (Angles at a point)
∠BCD
= 180° - 42° - 42°
= 96°
Answer(s): (a) 120°; (b) 96°