How do you find the perimeter of a polygon?

To find the perimeter of a polygon, add the lengths of each side together. The sum is the total perimeter.

1. Identify the lengths of each side of the polygon

   Some polygons are regular, with the lengths of each side equal to the lengths of other sides. Other polygons are irregular, requiring each side to be identified separately. Be certain you have the lengths of all the sides. Also, be certain that each side's length is expressed in identical units.

2. Calculate any missing information

   If necessary, calculate the lengths of any sides where the lengths are not given. Depending on the difficulty and irregularity of the polygon, this can be an easy or difficult process.

3. Add the lengths of all the sides

   For regular polygons, there are formulas to make the addition easier and more predictable. Although these formulas can save some time, they are not necessary. For both regular and irregular polygons, simply add the lengths of all the polygon's sides.

4. Express the perimeter's measurement correctly

   The perimeter of a polygon is expressed in the same measurement units as the sides' lengths. For example, if the sides are all measured in inches, then the perimeter is also expressed in inches.