Perimeter Formulas

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Introduction
This page contains the perimeter formulas for square, rectangle, triangle, and parallelogram. Examples are given to show you how to use these formulas.
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Square

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Formula
square with the sides L
formula for the perimeter of a square
The lesson on the perimeter of a square will provide the explanation and examples needed to understand this formula. Here's the summary:

All the sides (edges) of a square have the same length. If each side has the length L, the formula for the perimeter, P will be:
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Example
Given a square where the side lengths are 3cm. Find the perimeter of this square.
Using the formula for the perimeter of a square

Rectangle

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rectangle with width w and length l
Formula
The lesson on the perimeter of a rectangle will explain the basics needed to use this formula. Here's the summary:

If a rectangle has the length l, and the width w, the perimeter P, will be:
formula for the perimeter of a rectangle
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Example
Given a rectangle with the length of 5ft and the width of 3ft. Find its perimeter.
Using the formula for the perimeter of a rectangle

Triangle

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a circle with the radius r
Formula
The lesson on the perimeter of a triangle will explain the basics behind this formula. Here's the summary:

For a triangle with the side lengths of a, b and c, its perimeter P, will be: 
formula for the perimeter of a triangle

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Example
Given a triangle with the side lengths of 3cm, 4cm and 5cm. Find the perimeter of the triangle.
Using the formula for the perimeter of a triangle

Parallelogram

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Formula
a parallelogram with the base b and height h
The lesson on the perimeter of a parallelogram will explain the basics. Here's the summary:

For a parallelogram with side lengths of a and b, the perimeter P, is given as:
formula for the perimeter of a parallelogram

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Example
Given a parallelogram with the side lengths of 8 inches and 6 inches. Find the perimeter of this parallelogram. 
Using the formula for the perimeter of a parallelogram
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