Answer:
![\boxed {\tt 36 \ centimeters}](https://img.qammunity.org/2021/formulas/mathematics/college/rnnc1f48q9e423r9nifvijwtxw7wf5t8cd.png)
Explanation:
The perimeter is the sum of all the side lengths and a square has 4 equal sides.
The perimeter of a square can be found by adding the side length 4 times or multiplying the side length by 4.
![p=4s](https://img.qammunity.org/2021/formulas/mathematics/college/yiirz6ofp6zkvzxx41wmpwi93i76opexrm.png)
The side length is 9 centimeters.
![s= 9 \ cm](https://img.qammunity.org/2021/formulas/mathematics/college/bvo221ovnwbcff4co4ylwtkl16msq7b12l.png)
Substitute the value into the formula.
![p=4(9 \ cm)](https://img.qammunity.org/2021/formulas/mathematics/college/zj7rrspu9ml07cc8ozjilwklryzbii0ax1.png)
Multiply
![p= 36 \ cm](https://img.qammunity.org/2021/formulas/mathematics/college/it46l1igoxzf6j1wd0ifyaxi8doxxl7742.png)
The perimeter of a square with a side length of 9 centimeter is 36 centimeters.