Let's recall that for finding the length of each side of the polygon, we can use the following formula:
The polygon given is REGULAR, so it will be easier to calculate the perimeter.
Side QR = 1 - (-3) = 1 + 3 = 4 (We use only the x values, because y is constant)
Side RS = 2 - -(2) = 2 + 2 = 4 (We use only the y values, because x is constant)
Side ST = 1 - (-3) = 1 + 3 = 4 (We use only the x values, because y is constant)
Side QT = 2 - (-2) = 2 + 2 = 4 (We use only the y values, because x is constant)