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

Example Questions

Example Question #2 : 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 #1 : 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