Answer:
each side of the square is 25cm
Explanation:
this is because of two things:
1. a square has equal sides
2. the perimeter is all the sides added together.
so if you call the length of one side x, you can make this equation:
x + x + x + x = 100
combine like terms
4x = 100
divide both sides by 4
x = 100/4
x = 25