The length is 90 feet. We know that the length is equal to 3 times the width so we can express it as “3w” and the width as “w”. Since the perimeter is 240 feet, the equation we can use to find the length is: 3w + w + 3w + w =240. Simplify that into 8w = 240 after, then solve. You’ll get w = 30. That’s not all though. Since the length is 3w, we have to multiply 30 by 3, which is 90 feet. And to prove it’s correct, just add 90 + 90 + 30 + 30 and it’ll add up to 240 feet