The perimeter of a rectangle can be determined as the sum of twice its width and twice its length, following the formula:
![P=2w+2l](https://img.qammunity.org/2023/formulas/mathematics/college/gpuh5jkz5qmjnfrixwjvd1tfe9tqk98jbp.png)
If you know the perimeter and length of a rectangle, you can determine its width using the formula.
The first step is to write the formula for w:
-pass 2l to the left side of the equal sign by applying the opposite operation to both sides of it:
![\begin{gathered} P-2l=2w+2l-2l \\ P-2l=2w \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/3r0qujsm3hdzlu3hoaxsdwo91mmrc5p3cz.png)
-divide both sides by 2
![\begin{gathered} 2w=P-2l \\ (2w)/(2)=(P-2l)/(2) \\ w=(P-2l)/(2) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/90hth4j5sz0tr4l9zba2ez3onhcpn9swhk.png)
You know that the rectangular garden has a perimeter of P=370ft, and its length is l=98ft, replace both values on the formula obtained for w:
![\begin{gathered} w=(P-2l)/(2) \\ w=(370-2\cdot98)/(2) \\ w=(370-196)/(2) \\ w=(174)/(2) \\ w=87 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/xi1uesd8kgje65a0iuusolw8wektqyhcy6.png)
The width of the rectangular garden is 87ft