Question:
If two adjacent angles of a parallelogram are in the ratio 2 : 3, then the measure of angles are
(a) 72°, 108°
(b) 36°, 54°
(c) 80°, 120°
(d) 96°, 144°
Solution:
(a) Let the angles be 2x and 3x.
Then, 2x + 3x = 180° [ adjacent angles of a parallelogram are supplementary]
=> 5x = 180°
=> x = 36°
Hence, the measures of angles are 2x = 2 x 36°= 72° and 3x = 3×36°= 108°