A = 480
W = x
L = 11/5x
therefore 480 = 11/5xx
480 = 11/5x^2
4805 = 11x^2
2400/11 = x^2
\(+ or-\sqrt{2400/11} = x\)
However we can't have a negative width so width is \(\sqrt{2400/11}\)
Sub this into the length equation to find length \(\frac{11}{5} * \sqrt{2400/11}\)