Answer:
25 feet.
Step-by-step explanation:
Given : The perimeter of a square is 100 feet .
The area is 625 square feet .
To Find: What is the length of each side?
Solution:
Let the side of square be x
Formula of perimeter of square = 
Perimeter of square = 
The perimeter of a square is 100 feet .
So, 


Area of square = 
= 
= 
The calculated area is same as the given area.
Hence the side of the square sis 25 feet.