EFGH is a quadrilateral and OEHG is a trapezium in which OE // HG and ∠FEH = 111°, ∠EHG = 128°, ∠FGH = 66° and HG = HE. Find
- ∠EFO
- ∠HEO
- ∠EGH.
(a)
∠EFO
= 360° - 128° -111° - 66°
= 55° (Sum of angles in a quadrilateral)
(b)
∠HEO
= 180° - 128°
= 52° (Interior angles, EO//HC)
(c)
∠EGH
= (180° - 128°) ÷ 2
= 52 ÷ 2
= 26° (Isosceles triangle)
Answer(s): (a) 55°; (b) 52°; (c) 26°