Question

Type the correct answer in the box. If cos x = sin(20 + x)° and 0° < x < 90°, the value of x is °.

Answer 1

x = 35 degrees.

Explanation:

cos x = sin(20 + x)

Using the identity cos x = sin(90 - x):

20 + x = 90 - x

2x = 70

x = 35 degrees (answer).

Answer 2

Value of x is 35°.

Explanation:

Given:

cos x = sin ( 20 + x )

To find: Value of the x.

We know that
`sin\,(90-\theta)=cos\,\theta`

Consider,

cos x = sin ( 20 + x )

sin ( 90 - x ) = sin ( 20 + x )

Comparing both sides,

90 - x = 20 + x

-x - x = 20 - 90

-2x = -70

x = 35°

Therefore, Value of x is 35°.