Question

Which of the following gives the value of x in the given expression?

$4^x$ = 64

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

The correct option is C 3

The given expression is $4^x$ = 64

Let us substitute x = 1 in the given expression.
$4^1$ = 4
This does not satisfy the RHS, 64, of the given expression.

Let us substitute x = 2 in the given expression.
$4^2$ = 4 $\times$ 4 = 16
This does not satisfy the RHS, 64, of the given expression.


Let us substitute x = 3 in the given expression.
$4^3$ = 4 $\times$ 4 $\times$ 4 = 64
This satisfies the RHS, 64, of the given expression.

Let us substitute x = 5, in the given expression.
$4^5$ = 4 $\times$ 4 $\times$ 4 $\times$ 4 $\times$ 4= 1024
This does not satisfy the RHS, 64, of the given expression.

Hence, the value of x in the given expression is 3.