Three straight lines EF GH and LK interest at O... - JAMB Mathematics 2005 Question

∠GOK = 85^o (vertical opposite angle ∠s)

∠EOG + ∠GOK + ∠KOF = 180 (∠s on a straight line)

∠EOg + 85^o + 52^o = 180^o

∠EOG + 137^o = 180^o

∠EOG = 43^o