# If sec 4A = cosec (A – 20°), where 4A is an acute angle, find the value of A

**Solution:**

We use the basic properties of trigonometric ratios, sec and cosec to solve the given problem.

Given that, sec 4A = cosec (A - 20°) ….(i)

By using property in equation (i) we get:

cosec (90° - 4A) = cosec (A - 20°)

90° - 4A = A - 20°

5A = 110°

A = 110°/5

A = 22°

**Video Solution:**

## If sec 4A = cosec (A - 20°), where 4A is an acute angle, find the value of A

### Maths NCERT Solutions Class 10 - Chapter 8 Exercise 8.3 Question 5:

If sec 4A = cosec (A - 20°), where 4A is an acute angle, find the value of A

If sec 4A = cosec (A - 20°), where 4A is an acute angle, then the value of A is 22°