# ISEE Upper Level Math : How to find the perimeter of a parallelogram

## Example Questions

### Example Question #5 : Parallelograms The area of the Parallelogram is . Give its perimeter in terms of .      Explanation:

The height of the parallelogram is , and the base is . By the 45-45-90 Theorem, . Since the product of the height and the base of a parallelogram is its area,   Also by the 45-45-90 Theorem, , and The perimeter of the parallelogram is ### Example Question #6 : Parallelograms Calculate the perimeter of the above parallelogram if .      Explanation:

By the 45-45-90 Theorem,  The perimeter of the parallelogram is ### Example Question #7 : Parallelograms Calculate the perimeter of the above parallelogram if .      Explanation:

By the 30-60-90 Theorem: , and The perimeter of the parallelogram is ### Example Question #8 : Parallelograms

Find the perimeter of a parallelogram with a base of 6in and a side of length 8in.      Explanation:

A parallelogram has 4 sides.  A base (where the opposite side is equal) and a side (where the opposite side is equal).  So, we will use the following formula: where b is the base and s is the side of the parallelogram.

We know the base has a length of 6in.  We also know the side has a length of 8in.

Knowing this, we can substitute into the formula.  We get   