A parallelogram is a quadrilateral with opposite sides parallel.

Note that this results in the opposite sides also being congruent.

Given the following:

m: The length of a side of the parallelogram

n: The length of a side adjacent to side m of the parallelogram

h: The height of the parallelogram

b: The base of the parallelogram

P: The perimeter of the parallelogram

A: The area of the (interior of the) parallelogram

P = 2m + 2n    or    P = 2(m + n)

A = bh