Answer:
m∠x = 75°
Explanation:
Since sum of all angles in a quadrilateral EVWX = 360°
m∠E + m∠V + m∠W + m∠X = 360°
Since ∠X + ∠V = 180°
m∠E + m∠W = 180°
8x - 12 + 5x - 3 = 180
13x - 15 = 180
13x = 180 + 15 = 195
x = 195/13 = 15
Therefore ∠X = 5×15 = 75°