So, the measure of Angle A be '3x'. Since ABCD is a parallelogram, so the measure of opposite angle is equal and consecutive angles are supplementary. On putting the values, we get; Hence The measure of ∠A, ∠B, ∠C and ∠D are 135°, 45°, 135° and 45° respectively.
(Here you go, sorry if this didn’t help)
