Formula

Area of a Square

A square is a rectangle in which the length and width are equal. If the side length is denoted by ss, then the area of the square is:

A=s2A = s^2

When the area is known and the side length is needed, the formula is solved for ss by taking the square root of both sides:

A=s2A = s^2

A=s2\sqrt{A} = \sqrt{s^2}

A=s\sqrt{A} = s

Thus the side length formula is:

s=As = \sqrt{A}

The first formula gives the area when the side length is known; the second gives the side length when the area is known. Because the area must be positive, the principal (positive) square root is used.

Image 0

0

1

Updated 2026-04-21

Contributors are:

Who are from:

Tags

OpenStax

Elementary Algebra @ OpenStax

Ch.9 Roots and Radicals - Elementary Algebra @ OpenStax

Algebra

Math

Prealgebra

Related
Learn After