The length of a rectangle is 3 cm longer than its width. If the perimeter of the rectangle is 54 cm, find its length and width.

Mathematics · Middle School · Sun Jan 24 2021

Answered on

Given the statement:

The length of a rectangle is 3 cm longer than its width.

Perimeter of the rectangle = 54 cm

Find the length and the width rectangle.

Formula for the perimeter of the rectangle:

P = 2l + 2w

Solution:

In order to find the length and the width rectangle, we simply represent the given values.

Width = x

Length = 3 + x

Represent the values in the formula for the perimeter of the rectangle.

P = 2l + 2w

54 = 2(3 + x) + 2x

54 = 6 + 4x + 2x

54 = 6 + 6x

Transpose 6 to the other side of the equation, hence it must be taken to note that in transposing a number, the sign changes.

6x = 54 -6

6x = 48

Divide both sides by 6 in order to determine the value of x.

6x/6 = 48/6

x = 8

Wdith = 8 cm

Length = 3cm + 8 cm

Length = 11 cm

Final answer:
Width = 8 cm

Length = 11 cm