Answer:
y = 75
Explanation:
The sum of the angles in a quadrilateral = 360°
∠DGF and 80° form a straight angle and are supplementary, hence
∠DGF = 180° - 80° = 100°
Subtract the sum of the 3 angles from 360 for the value of y
y = 360 - (65 + 120 + 100) = 360 - 285 = 75