Answer:
w = 90 feet and l = 490 feet
Step-by-step explanation:
First, determine what you're given:
Perimeter = 1,160 feet
Perimeter = 1,160 feetlength = (w)idth + 400
idth + 400width = w
Next, solve for the length and the width using the perimeter equation (2l + 2w = Perimeter)
2(400+w) + 2w = 1,160 feet
(800 + 2w) + 2w = 1,160 feet
800 + 2w + 2w = 1,160 feet
800 + 4w = 1,160 feet
{ Subtract 800 from both sides }
4w = 360 feet
{ Divide both sides by 4 to isolate w }
w = 90 feet
Finally, you've solved for the width which is 90 feet. Plug this back into your equation for length;
[ l = 400 + w ]
l = 400 + (90)
l = 490 feet
Since it never hurts to check;
2l + 2w = 1,160 feet
2(400+w) + 2w = 1,160 feet
2(400+90) + 2w = 1,160 feet
✅2(490) + 2(90) = 1,160 feet
