PSLEIn the figure, ABCD is a parallelogram. AYD and YCZ are straight lines. ∠ZCD = 149°, ∠ADC = 48° and ∠ACY = 19°.
- Find ∠BCZ.
- Find ∠BAC.
(a)
∠BCD
= 180° - 48°
= 132° (Interior angles)
∠BCZ
= 360° - 149° - 132°
= 79° (Angles at a point)
(b)
∠DCY
= 180° - 149°
= 31°(Angles on a straight line)
∠BAC
= ∠ACD
= 31° + 19°
= 50° (Alternate angles)
Answer(s): (a) 79°; (b) 50°