The measures of the interior angles in a quadrilateral add up to 360 degrees, so make angles A, B, and C add up to 360 in an equation. Solve for x, the missing angle.
34 + 108 + 65 + x = 360
Combine like terms.
207 + x = 360
Subtract 207 from both sides.
x = 153
C) 153 degrees is your answer.
