Question 280333
let x = L
y = W
P = 380 

{{{2x + 2y = 380 }}}
{{{x = 3y - 70}}}
{{{2(3y-70) + 2y = 380}}}
{{{6y-140+2y = 380}}}
{{{8y-140+140 = 380 + 140}}}
{{{8y/8=520/8}}}
{{{y=65}}}