Question 837908
For a rectangle,
{{{P=2*(L+W)}}}
{{{A=L*W}}}
For this rectangle,
{{{L=W+3}}}
and
{{{L*W=2*(L+W)}}}
Substituting,
{{{(W+3)W=2(W+3+W)}}}
{{{W^2+3W=4W+6}}}
{{{W^2-W-6=0}}}
{{{(W-3)(W+2)=0}}}
Only the positive solution makes sense for this problem.
{{{W-3=0}}}
{{{W=3}}}
{{{L=W+3=6}}}