In the figure, CDEF is a quadrilateral where ∠CDE = 128° and ∠DEF = 114°. ∠EFG = 73° and DE = EF. The point G on CF is such that DG is parallel to EF. Calculate
- ∠DFG
- ∠DCG
(a)
∠EFD
= (180° - 114°) ÷ 2
= 33° (Isosceles triangle)
∠DFG
= 73° - 33°
= 40°
(b)
∠DCG
= 360° - 114° - 73° - 128°
= 45° (Sum of angles in a quadrilateral)
Answer(s): (a) 40°; (b) 45°