Answer:
Angle B = x = 50°
Angle A = 115°
Angle D = 90°
Explanation:
Sum of the interior angles of a quadrilateral = 360°
Therefore:
(3x - 35)° + x + 90° + 105° = 360°
Solve for x
3x - 35 + x + 90 + 105 = 360
Add like terms
4x + 160 = 360
Subtract 160 from each side
4x = 360 - 160
4x = 200
Divide both sides by 4
x = 50
Angle C = x = 50°
Angle A = 3x - 35
Plug in the value of x
Angle A = 3(50) - 35 = 150 - 35
Angle A = 115°