Learn About Perimeter of Irregular Shapes Perimeter of other shapes. So before we begin, let’s talk about the perimeter. So remember that a perimeter is the distance around the outside of a closed shape. So to find the perimeter of a polygon, we add the lengths of all its sides. So if you find the perimeter of a polygon, you add the lengths of all the sides. Now, also remember that in the unit of length, you have to also mention what the unit of length is. So if it’s measured in centimeters, you have to label it centimeters, inches, feet, etc. So remember that the perimeter, P for perimeter is equal to the sum of all the sides. Alright, so let’s take a look at our first figure, figure 1. So here we have figure 1, this figure is a polygon with a side of 1 meter 150 centimeters, 200 centimeters 2 meters, 2.5 meters. So to find the perimeter, we first need to write all the side lengths in the same unit because you notice, we have meters and centimeters so they all have to be in the same unit. So we have to convert 150 centimeters and 200 centimeters into meters. So the first thing that we need to do is convert. So we need to convert the centimeters into meters. So we know that 1 meter equals 100 centimeters, or we can say 100 centimeters equals 1 meter. So therefore, to convert 150 centimeters, we know that 150 centimeters would equal 150 meters divided by 100. Because to convert 150 centimeters, we divide 150 by centimeters. So therefore, 150 centimeters will equal 1.5 meters. Similarly, we need to convert 200 centimeters. So 200 centimeters will equal 2 meters if we divide it by 100. Alright, so we just converted our centimeters in to meters. Alright, so now, we need to find the perimeter of this object. So remember that the perimeter is the sum of all the sides. So to find the perimeter, it’s going to equal to sum of all the sides. So we’re going to go ahead and add all the sides up. So we have 1.5 + 2 +2 +2.5. So if we add these up, we get 9 meters. So the perimeter of this object, this figure here is 9 meters. Let’s move on to figure 2. So figure 2 is a polygon with six sides. Each sides measures 5 feet. Remember that a polygon with six sides is a hexagon. So this shape or this figure is a hexagon. It has six sides. Now, the perimeter, remember, is the distance around the outside of a closed figure so the perimeter is the sum of all the sides. Since the measure of all these sides are equal in length, this is a regular polygon. So the perimeter of a regular polygon will be the side + side—So we’re adding all the sides, so all six sides. Or we can say 6 x S. So the perimeter of a hexagon would be 6x. So to find the perimeter of the hexagon, we’re going to plug in the side with the 5. So the perimeter of the hexagon is 6 x S, and we know that S = 5, so it would be 6 x 5 which gives us 30 feet. Remember to mention your units. So the perimeter of this hexagon is 30 feet. Alright, remember that the perimeter of a regular hexagon of N equal sides with each sides of S is N x S. So anytime you have a regular hexagon, the perimeter is N x S where S are the sides. So some things to keep in mind and remember is that the perimeter is the distance around the outside of a closed shape or a closed figure. Remember that the perimeter is the sum of all the side lengths of a polygon, so you add the lengths of all the sides. The perimeter of a regular polygon of N equal sides is with the S = S is N x S. Always remember—so this is a regular polygon. And also remember to name the unit of length used to measure your figure or shape.