HJKL and CDEK are rhombuses. Find ∠CGJ.
∠CJL
= (180° - 120°) ÷ 2
= 30° (Isosceles triangle)
∠EDF
= 180° - 90° - 13°
= 77° (Angles sum of triangle)
∠KCJ = ∠EDF
= 77° (Corresponding angles)
∠CGJ
= 180° - 77° - 30°
= 73° (Angles sum of triangle)
Answer(s): 73°