Calculate Square Side Length: Finding Dimensions When Area = 81

Question

A square has an area of 81.

How long are its sides?

00:00 Find the side of the square

00:03 Use the formula for calculating the area of a square (side squared)

00:08 Substitute appropriate values and solve for the side

00:15 Extract the root

00:21 And this is the solution to the problem

Remember that the area of a square is equal to the side of the square raised to the second power.

Formula for the area of the square:

$A=L^2$

We calculate the area of the square:

$81=L^2$

We calculate the root:

$\sqrt{81}=a$

$9=a$

$9$