How Do You Calculate the Area of a Rectangle?

Compared to other geometric figures, the rectangle is one of the simplest to work with.

One of the most frequent questions that comes up in exams is related to how to calculate the area of the rectangle.

Before we focus on it, let's do a brief review.

The formula for calculating the area of a rectangle is as follows:

A1 -Base DC x Height AD = Area of the rectangle

Base DC×Height AD=Area of rectangle Base~DC\times Height~AD=Area~of~rectangle

Practice Area of a Rectangle

Examples with solutions for Area of a Rectangle

Exercise #1

Look at rectangle ABCD below.

Side AB is 10 cm long and side BC is 2.5 cm long.

What is the area of the rectangle?
1010102.52.52.5AAABBBCCCDDD

Video Solution

Step-by-Step Solution

Let's begin by multiplying side AB by side BC

If we insert the known data into the above equation we should obtain the following:

10×2.5=25 10\times2.5=25

Thus the area of rectangle ABCD equals 25.

Answer

25 cm²

Exercise #2

Look at the rectangle ABCD below.

Side AB is 6 cm long and side BC is 4 cm long.

What is the area of the rectangle?
666444AAABBBCCCDDD

Video Solution

Step-by-Step Solution

Remember that the formula for the area of a rectangle is width times height

 

We are given that the width of the rectangle is 6

and that the length of the rectangle is 4

 Therefore we calculate:

6*4=24

Answer

24 cm²

Exercise #3

Look at the rectangle ABCD below.

Side AB is 4.5 cm long and side BC is 2 cm long.

What is the area of the rectangle?
4.54.54.5222AAABBBCCCDDD

Video Solution

Step-by-Step Solution

We begin by multiplying side AB by side BC

We then substitute the given data and we obtain the following:

4.5×2=9 4.5\times2=9

Hence the area of rectangle ABCD equals 9

Answer

9 cm²

Exercise #4

The width of a rectangle is equal to 15 cm and its length is 3 cm.

Calculate the area of the rectangle.

Video Solution

Step-by-Step Solution

To calculate the area of the rectangle, we multiply the length by the width:

15×3=45 15\times3=45

Answer

45

Exercise #5

Given the following rectangle:

111111777AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

11×7=77 11\times7=77

Answer

77

Exercise #6

Given the following rectangle:

222555AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

2×5=10 2\times5=10

Answer

10

Exercise #7

Given the following rectangle:

666999AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

We will use the formula to calculate the area of a rectangle: length times width

9×6=54 9\times6=54

Answer

54

Exercise #8

Given the following rectangle:

888444AAABBBDDDCCC

Find the area of the rectangle.

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

4×8=32 4\times8=32

Answer

32

Exercise #9

ABCD is a rectangle.

Given in cm:

AB = 7

BC = 5

Calculate the area of the rectangle.

777555AAABBBCCCDDD

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

AB×BC=7×5=35 AB\times BC=7\times5=35

Answer

35

Exercise #10

Look at the rectangle ABCD below.

Given in cm:

AB = 10

BC = 5

Calculate the area of the rectangle.

101010555AAABBBCCCDDD

Video Solution

Step-by-Step Solution

Let's calculate the area of the rectangle by multiplying the length by the width:

AB×BC=10×5=50 AB\times BC=10\times5=50

Answer

50

Exercise #11

The area of the rectangle below is equal to 63.

AC = 7

How long is side AB?

777AAABBBDDDCCC63

Video Solution

Step-by-Step Solution

We use the formula to calculate a rectangle: length times width:

AB×AC=S AB\times AC=S

We place the existing data into the formula:

AB×7=63 AB\times7=63

7AB=63 7AB=63

We divide both sides by 7:

AB=9 AB=9

Answer

9

Exercise #12

The area of the rectangle below is equal to 44.

AC = 4

Calculate AB.

444444444AAABBBDDDCCC

Video Solution

Step-by-Step Solution

The area of the rectangle is equal to its length multiplied by its width.

Let's begin by substituting the known data into the formula:

S=AB×AC S=AB\times AC

44=AB×4 44=AB\times4

Let's now divide both sides by 4:

AB=11 AB=11

Answer

11

Exercise #13

The area of the rectangle below is equal to 24.

AC = 3

What is the length of side AB?

242424333AAABBBDDDCCC

Video Solution

Step-by-Step Solution

The area of the rectangle is equal to its length multiplied by its width.

Let's begin by inserting the known data into the formula:

S=AB×AC S=AB\times AC

24=AB×3 24=AB\times3

Let's now divide both sides by 3:

AB=8 AB=8

Answer

8

Exercise #14

The area of the rectangle below is equal to 55.

AC = 5.5

Calculate the length of side AB.

555555AAABBBDDDCCC5.5

Video Solution

Step-by-Step Solution

The area of a rectangle is equal to its length multiplied by its width.

Hence let's begin by inserting the known data into the formula:

S=AB×AC S=AB\times AC

55=AB×5.5 55=AB\times5.5

Let's now divide both sides by 5.5:

AB=10 AB=10

Answer

10

Exercise #15

The area of the rectangle below is equal to 84.

AC = 7

What is the length of side AB?

848484777AAABBBDDDCCC

Video Solution

Step-by-Step Solution

The area of the rectangle is equal to its length multiplied by its width.

Let's begin by inserting the known data into the formula:

S=AB×AC S=AB\times AC

84=AB×7 84=AB\times7

Let's now divide both sides by 7:

AB=12 AB=12

Answer

12