Question 1030924
{{{A=L*W=7056}}}
{{{P=2L+2W=2(L+W)}}}
From above,
{{{L=7056/W}}}
Substituting,
{{{P=2(7056/W+W)}}}
To minimize, take the derivative with respect to W.
{{{dP/dW=2(-7056/W^2+1)}}}
Set it equal to zero,
{{{-7056/W^2+1=0}}}
{{{7056/W^2=1}}}
{{{W^2=7056}}}
{{{W=84}}}
So then,
{{{L=7056/84}}}
{{{L=84}}}
So,
{{{P[min]=2(84+84)}}}
{{{P[min]=2(168)}}}
{{{P[min]=336}}}{{{m}}}