Answer:
side length = 4
Step-by-step explanation:
Let x = the side length
Area is x•x, which is x^2.
Perimeter is x+x+x+x, which is 4x.
x^2 = 4x
x^2 - 4x = 0
Factor.
x(x-4) = 0
x = 0 or x = 4
Discard 0 as an answer as it is not useful.
x = 4.
Area = 4^2 = 16
Perimeter = 4(4)= 16
The side length is 4.
