We know that the area is 20.
Since 20 is a small number: lets list out possible combinations of lengths and widths.
1 * 20
2 * 10
4 * 5
L = 7 + 3w
lets see which on makes sense.
L = 7 + 3w
20 = w7 + 3w^2
3w^2 + 7w -20 = 0
(3w - 10)(w - 2)
w can equal 10/3 or 2.
So the dimensions: are Width = 2 Length = 10
