There is a measure of the area around a two-dimensional shape.The perimeter is the total length of the outline, including the two widthwise borders and two diagonal borders.You add the dimensions that make up the shape's outer edge to determine the perimeter.There are many applications for being able to find the perimeter of a shape.You want to build a fence around your backyard.To purchase materials, you need to know how much fencing you'll need, as well as the perimeter of the area you want to fence.
Step 1: Determine how long each side is.
Since perimeter is a measure of the outline of a two-dimensional figure, you don't usually need a formula to find it.You need to know the length of all the sides of the shape.To determine the perimeter of a pentagon, you need to know the length of each side.You can still find the perimeter if you know the length of each side.
Step 2: Add the length of the sides together.
To find the perimeter of non-circular objects, you need the sum of all the side lengths.A, B, C, D, and E are the lengths of the irregular pentagon.
Step 3: Use variables to deal with them.
When working with variables, you can still find perimeter.Say you have a triangle with the side lengths 14a, 11b, and 7a and you want to combine them.
Step 4: Units of measurement should be paid attention to.
If you don't know what unit of measurement you're working with, finding the perimeter of an object will not do you much good in a real world application.The P is 14 cm if each side was measured in centimeters.
Step 5: The circle has a perimeter.
Some regular shapes have formulas that make it quicker to find the figure's perimeter.There are circles that need a formula to find perimeter.The circle's circumference is called the perimeter.The equation C (circumference) is used to find the circle's diameter.The circle's radius is the length of a line segment from the center to the perimeter.For simpler equations, use the truncated version.
Step 6: Find the center of the triangle.
The equation P is a + b + c for a triangle.If a triangle has dimensions of 20 cm, b is 11 cm and c is 9 cm then P is 20 + 11 + 9.
Step 7: Find the perimeter of the square.
Because a square has four sides of the same length, you can use a simple equation to find the length of one side.There is a square where x is 3 cm and P is 4 cm.
Step 8: You can find the perimeter of a rectangle.
The width of one side is the same as the length of the other, so the equation P is 2l + 2w.The equation P is 2(l + h) and will give you the same result: 2(13).
Step 9: Find the perimeter of other quadrilaterals.
A quadrilateral is a two-dimensional shape with four closed, straight sides.This also includes kites, rhombuses, and parallelograms.The same equation as a square can be used for a quadrilateral with no equal sides.For quadrilaterals where the widthwise sides are the same, use the equations 2a + 2b.