Area of Rectangle Formula

This figure illustrates the area of a rectangle formula.

Formula

Summary

The area of a rectangle is given by the width multiplied by the height.

Expression Description
The area of the rectangle.
The width of the rectangle.
The height of the rectangle.

Usage

The Area of a rectangle is given by its width multiplied by its height. For example, the area of a rectangle with with a width of three units and a height of four units is equal to twelve units squared.

Examples

Example 1

Area of Rectangle Width 4 Height 3

This example shows how to calculate the area of a rectangle with a width of and a height of .

Steps

  1. Start by setting up the formula.

  2. Substitute the values for the width and height into the formula.

  3. Evaluate the multiplication.

    The area of the rectangle is equal to units squared.

Example 2

Area of Rectangle Width 5 Height 4

This example shows how to calculate the area of a rectangle with a width of and a height of .

Steps

  1. Start by setting up the formula.

  2. Substitute the values for the width and height into the formula.

  3. Evaluate the multiplication.

    The area of the rectangle is equal to units squared.

Example 3

Area of Rectangle Width 3 Height 3

This example shows how to calculate the area of a rectangle with a width of and a height of .

Steps

  1. Start by setting up the formula.

  2. Substitute the values for the width and height into the formula.

  3. Evaluate the multiplication.

    The area of the rectangle (also a square) is equal to units squared.

Explanation

This figure illustrates the area of a rectangle formula.
Figure 1: Area of Rectangle Formula

The area of the rectangle formula can be verified first by counting individual square units and by using the properties of multiplication. For example, the area of a rectangle with a width and a height of is equal to units squared. This is verified, as shown below, by counting.

Area of Rectangle Formula Counting Explanation

The area of this rectangle can also be verified using the properties of multiplication. Namely, multiplication can be though of as a “groups of” operator. In this case, the area of the rectangle can be represented as groups of as shown below.

Area of Rectangle Formula Explanation

This corresponds to the arithmetic expressions below.