If the perimeter of a square is 36 cm, what is the length of one side?

To find the length of one side of a square when the perimeter is known, you can use the formula for the perimeter of a square. The perimeter ( P ) of a square is calculated as ( P = 4s ), where ( s ) is the length of one side.

In this case, you have the perimeter given as 36 cm. Setting up the equation based on the formula:

[ 4s = 36 ]

To isolate ( s ), divide both sides of the equation by 4:

[ s = \frac{36}{4} ]

Calculating this gives:

[ s = 9 \text{ cm} ]

Thus, the length of one side of the square is indeed 9 cm, confirming that the correct answer is this option.