Question

If two adjacent angles of a parallelogram are (5x – 5)° and (10x + 35)°, then the ratio of these angles is ______.

विकल्प

• 1 : 3

• 2 : 3

• 1 : 4

• 1 : 2

Answer 1

If two adjacent angles of a parallelogram are (5x – 5)° and (10x + 35)°, then the ratio of these angles is 1 : 3.

Explanation:

We know that, adjacent angles of a parallelogram are supplementary, i.e. their sum equals 180°.

∴ (5x – 5) + (10x + 35) = 180° 

⇒ 15x + 30° = 180°

⇒ 15x = 150°

⇒ x = 10°

Thus, the angles are (5 × 10 – 5) and (10 × 10 + 35), i.e. 45° and 135°.

Hence, the required ratio is 45° : 135°, i.e. 1 : 3.