3 Ways to Find the Perimeter of a Polygon
A polygon is a two-dimensional geometric shape made up of straight line segments that are joined together by vertices. The perimeter of a polygon is the sum of the lengths of its sides. Calculating the
perimeter is an essential skill in many areas, such as geometry, architecture, and construction. In this article, we will explore three different ways to find the perimeter of a polygon.
1. Using Side Lengths
When you know the lengths of all the sides of a polygon, calculating its perimeter becomes a straightforward task. Add up the lengths of all sides to determine the total perimeter. For example, if you have a square with side lengths of 4 units each, add 4 + 4 + 4 + 4 to get a total perimeter of 16 units.
2. Using Regular Polygons
A regular polygon is a shape where all sides and angles are equal. In such cases, finding the perimeter becomes even easier. Multiply the length of one side by the number of sides to calculate the perimeter. For instance, if you have an equilateral triangle with side lengths of 5 units each, multiply 5 by 3 (the number of sides) to get a total perimeter of 15 units.
3. Using Apothem and Side Lengths in Regular Polygons
If you know both the apothem (the distance from the center to the midpoint of any side) and one side length in a regular polygon, you can apply specific formulas to find its perimeter.
For even-sided polygons like squares or octagons, use this formula:
P = 2n * [s / (2 * tan(180° / n))]
Where P is the perimeter, n is the number of sides, s is one side length.
For odd-sided polygons like triangles or pentagons, use this formula:
P = n * [2 * a * tan(180° / n)]
Where P is the perimeter, n is the number of sides, and a is the apothem.
In summary, finding the perimeter of a polygon will depend on the information you have. Whether you know all the side lengths, work with a regular polygon, or have access to the apothem in addition to side lengths, remember that there are various ways to approach the task and effectively calculate a polygon’s perimeter.