Question

A square has an area of 81 square inches. What is its perimeter?

Answer 1

Step-by-step explanation:

In order to find the perimeter we need to find the length first ...

...Here, the area is already given ...

Area = 81 inches square

length = ?

Now....

( The formula of area is l × l )

$area = {l}^{2}$

$81 = {l}^{2}$

Now we should find square root of 81...

$l = \sqrt{81}$

$l \: = 9$

Now we find length so it's easy for us to find perimeter...

The formula of perimeter of square is 4l ..

= 4l

= 4 × 9

= 36 inches

hence the answer is 36 inches....

Answer 2

Area of square = $s^2$ where, $s$ is the side length of the square.

$81=s^2$

$9=s$

s must be positive since it is a side length, so the negative root of 81 is rejected.

Perimeter= $4s$

Perimeter= $4(9)=36inches$