The ratio of an angle and its comple-mentary angle is 2 : 7, then the

1.	The ratio of an angle and its comple-mentary angle is 2 : 7, then the angle is A) 70° B) 20° C) 110° D) 50°
Answer» Correct option is (B) 20° Let both angles are 2x and 7x. \(\because\) Both angles are complementary angles to each other. \(\therefore\) 2x+7x = \(90^\circ\) \(\Rightarrow\) 9x = \(90^\circ\) \(\Rightarrow\) x = \(\frac{90^\circ}9=10^\circ\) \(\therefore\) Required angle = 2x \(=20^\circ\) Correct option is B) 20°

The ratio of an angle and its comple-mentary angle is 2 : 7, then the angle is A) 70° B) 20° C) 110° D) 50°

Answer»

Correct option is (B) 20°

Let both angles are 2x and 7x.

\(\because\) Both angles are complementary angles to each other.

\(\therefore\) 2x+7x = \(90^\circ\)

\(\Rightarrow\) 9x = \(90^\circ\)

\(\Rightarrow\) x = \(\frac{90^\circ}9=10^\circ\)

\(\therefore\) Required angle = 2x \(=20^\circ\)

Correct option is B) 20°