Perimeter of a pentagon

The perimeter, P, of a pentagon is the distance roughly its 5 straight sides.

You are watching: How to find perimeter of pentagon


How you uncover the perimeter of a pentagon depends on what form of pentagon friend have and what is known around it.

Regular and also irregular pentagons

Regular pentagons have five congruent sides, 5 congruent internal angles, and also five congruent exterior angles. Choose all regular polygons, all the sides should be the exact same length, and all the angles have to be the very same measurement.

Irregular pentagons have 5 sides and also five angles, however neither the sides nor the angles are congruent. An rarely often, rarely polygon can have sides of five various lengths and angles of five various measures.

It is easier to find the perimeter of a continuous pentagon due to the fact that we have actually a formula. To find the perimeter that an rarely often rare pentagon, you have to measure and add up the five sides.

Perimeter of a pentagon formula

Using the perimeter of a pentagon formula, friend can find the perimeter of a continuous pentagon with relative ease. To find the perimeter that a consistent pentagon with sides of length, s, you use this formula:

P = 5 × s

In our formula, 5 is the number of sides, and also s is the length of the side that we know. As with with the perimeter of a square, or the perimeter of a polygon in general, you uncover the perimeter the a pentagon by including all the political parties together.

If you room finding the perimeter the a continuous pentagon, then you recognize that all five sides space equal lengths, therefore you have the right to simplify the formula making use of multiplication instead of addition.

If you favor to use the addition technique your perimeter for a continuous pentagon would look choose this:

P = s + s + s + s + s

You have an s for each side of the pentagon.


Perimeter that a continual pentagon example

Let"s pretend that we have a consistent pentagon and also that we recognize one side length is 3 cm. What is the perimeter of the pentagon?

If we understand one side of a constant pentagon, then we know the length of each side since a continual pentagon has actually equal sides. We can simply plug our known side right into our formula:

P = 5 × s

P = 5 × 3

P = 15

Knowing that the length of a next is 3 cm, we used the perimeter formula of a pentagon, we uncovered that the perimeter of this consistent pentagon is 15 cm.

See more: Is There A Limit To How Many Pages In An Envelope For 1 Stamp ?


Another important part of a pentagon is the apothem and also the area. Learn just how to uncover the area of a pentagon utilizing the area formula. Girlfriend can find the area of a constant pentagon or an rarely often, rarely pentagon.

Next Lesson:

Area of a Pentagon

What friend learned:

After functioning your method through this lesson, you must know:

How to discover the perimeter of a pentagonThe difference between regular and also irregular pentagonsHow to use the perimeter the a pentagon formula to uncover the perimeter of a consistent pentagon