Write the length as an expression containing the width.
The width of the rectangle is 13 cm.
Practice makes perfect
Let's label the length of the rectangle l and the width w. Using the information in the exercise, we can write an expression for l in terms of w.
Given Sentence:
The length of a rectangle is 5 cm longer
than twice the length of the width. [1em]
↓ [0.4em]
Equation:
l = 2 w + 5The length can be written as l =2w+5. To calculate the perimeter of a rectangle, we add twice its width to twice its length. With this information we can write the following equation.
P=2w + 2 l → P=2w + 2 (2w+5)
By setting P equal to 88 we can solve for w.
