Hi there!
If we know the perimeter of the lot, it's pretty easy to find the length and width. Since we know that the lot is a square, we know that all sides are the same. And there are four sides on a square. Using this information, we can get an equation: 60 = x + x + x + x. Then, we need to simplify and solve the equation: 60 = 4x | x = 15 feet. Therefore, the length and width of the lot is 15 feet.
Hope this helps!! :)
If there's anything else that I can help you with, please let me know!