In the figure, CDF is a triangle with DF = DC, while BCDE is a parallelogram and EDF is a straight line. Given ∠DEB = 92°, ∠ADF = 140° and ∠BAD = 57°, find
- ∠DCF
- ∠ADC
(a)
∠BED
= ∠CDF
= 92° (Corresponding angles)
∠DCF
= (180° - 92°) ÷ 2
= 44° (Isosceles triangle)
(b)
∠ADC
= 360° - 140° - 92°
= 128° (Angles at a point)
Answer(s): (a) 44°; (b) 128°