Question

Q9. Find the angle which is 30° less than twice its complement.
(a) 50°
(b) 40°
(c) 25°
(d) 50​

Answer 1

Step-by-step explanation:

Let the angle be x

complementary angles are those which add up to 90°

So, other angle will be (90°-x)

According to the question,

x=2(90°-x)-30°

x=180°-2x-30°

x=150-2x

3x=150

x=50

Thus 50° is answer..(a) option..

Answer 2

Answer:

A) 50

Step-by-step explanation:

Let’s make this clear.

Let the required angle be x. Then, since the other angle is complementary to x, the other angle is (90 - x).

With the given info, the equation is:-

$x = 2(90-x) - 30$

Upon simplification,

=> $x = 180 - 2x - 30$

=> $x + 2x = 180 - 30$

=> $3x = 150$

=> $x = \frac{150}{3}$

=> $x = 50$

Small correction to your question:-

Option D is 60 degrees.