PSLEIn the figure, ABCD is a parallelogram. AYD and YCZ are straight lines. ∠ZCD = 147°, ∠ADC = 44° and ∠ACY = 20°.
- Find ∠BCZ.
- Find ∠BAC.
(a)
∠BCD
= 180° - 44°
= 136° (Interior angles)
∠BCZ
= 360° - 147° - 136°
= 77° (Angles at a point)
(b)
∠DCY
= 180° - 147°
= 33°(Angles on a straight line)
∠BAC
= ∠ACD
= 33° + 20°
= 53° (Alternate angles)
Answer(s): (a) 77°; (b) 53°