A parallelogram has vertices at (1,2), (5,2), (-1,-3) and (3,-3). Find the perimeter to the nearest tenth.

Do I use the distance formula and if so, how?

Yes, use the distance formula to find the lengths of each of the four edges of the parallelogram, then add up those four lengths. For example, the length of the edge that goes from point (a,b) to point (c,d) is:


\sqrt{ (c-a)^2 + (d-b)^2 }