Answer :
Hey there! I'm happy to help!
All the sides of a square are the same. This means that you multiply one of the sides by itself to get the area, which is conveniently called squaring. To go backwards, you find the square root. We already know that 144 is 12×12, but if you didn't know you could do √144 on your calculator and get 12.
Since each side is 12, we multiply 12 by 4, giving us 48 feet as our perimeter.
Have a wonderful day! :D