Question

if the angle of a parallelogram is two-third of its adjacent angles, find the angles of the parallelogram.

Answer 1

Let ABCD a parallelogram with A = C and B = D. A = 2/3B.

let A = x
and B = 2/3x

A+B = 180° [Angle Sum Property]
x+2/3x = 180°
5/3x = 180°
x = 180 × 3/5
x = 108°

A = C = x = 108°

B = D = 2/3x =72°