Let the width = w.
Then the length is 3w - 5.
The area = LW = 28
w(3w - 5) = 28
3w^2 - 5w = 28
3w^2 - 5w - 28 = 0
(3w + 7)(w - 4) = 0
3w + 7 = 0 or w - 4 = 0
w = -7/3 or w = 4
The width of a rectangle cannot be a negative number, so we discard w = -7/3.
The width is 4 ft.
The length is 3w - 5 = 3(4) - 5 = 12 - 5 = 7
The length is 7 ft
Answer: The dimensions are length 7 ft and width 4 ft.
