Answer:
Width = 110 ft
Step-by-step explanation:
width = x
length = x + 300
To find the width, we use the formula for perimeter, substituting 1040 for perimeter, x + 300 for length, and x for width:
![P=2(l+w)\\\\1040=2[(x+300)+x]](https://tex.z-dn.net/?f=P%3D2%28l%2Bw%29%5C%5C%5C%5C1040%3D2%5B%28x%2B300%29%2Bx%5D)
Combine like terms inside the brackets:

Distribute the 2 within the parentheses:

Subtract 600 from both sides:

Divide both sides by 4:

Therefore, the width is 110 ft and the length is 410 ft. To verify, we can check that the perimeter equals 1,040 ft.
