PSLEIn the figure, ABCD is a parallelogram. AYD and YCZ are straight lines. ∠ZCD = 153°, ∠ADC = 44° and ∠ACY = 18°.
- Find ∠BCZ.
- Find ∠BAC.
(a)
∠BCD
= 180° - 44°
= 136° (Interior angles)
∠BCZ
= 360° - 153° - 136°
= 71° (Angles at a point)
(b)
∠DCY
= 180° - 153°
= 27°(Angles on a straight line)
∠BAC
= ∠ACD
= 27° + 18°
= 45° (Alternate angles)
Answer(s): (a) 71°; (b) 45°