You know that a square has four even sides, and that the perimeter of a shape is l+w+l+w, where l means length and w means width.
The perimeter of a square can also just be 4 times any of the side lengths, as they're all the same. From this reasoning, you can find the length of any/all sides by dividing the perimeter by 4.
28/4=7, so the side length of the square would be 7 feet.
Area is equal to length times width. And in the case of a square, the area would be length-squared.
7x7=49
The area of a square with a perimeter of 28 feet is 49 feet. Hope this helps :-)
