Question

The perimeter of a rectangular swimming pool is $200$ feet. The length is $40$ feet more than the width. Find the length and width.

Short answer

Length is$70$feet and width is$30$feet.

Step-by-step solution

Step 1. Given information

The perimeter of a rectangular swimming pool is $200$feet. The length is $40$feet more than the width.

Step 2. Finding unknowns

Let the width of rectangle is $b=x$

Therefore the length is $x+40$

According to the question,

$$\begin{gathered} 2(l+b)=200 \\ 2(x+40+x)=200 \\ 2(2x+40)=200 \\ 4x+80=200 \\ 4x=120 \\ x=30=b \end{gathered}$$

And the length is

$$\begin{gathered} l=x+40 \\ l=30+40 \\ l=70 \end{gathered}$$