Question 938295
For a rectangle,
{{{P=2(L+W)=72}}}
{{{L+W=36}}}
.
..
{{{L=3W}}}
Substitute,
{{{3W+W=36}}}
{{{4W=36}}}
{{{W=9}}}
So then,
{{{L=3(9)}}}
{{{L=27}}}