Since you want length in meters, we assume the perimeter is expressed in meters and the area is expressed in square meters. For side length s, the given relation is
4s = s² +2
Adding 2 - 4s to both sides of this equation lets us complete the square.
2 = s² -4s +4
2 = (s -2)²
Now, we can take the square root and add 2 to get ...
±√2 = s -2
2 ±√2 = s
One side of the square can be either 2 - √2 meters ≈ 0.5858 meters, or it can be 2 + √2 ≈ 3.4142 meters. (There are two possible answers.)
