Question 1151022
If "restricted to" means equal to then the system of equations {{{system(L+4x=108,A=2x^2+4Lx)}}}   fits the description.


Substituting and simplifying gives {{{A=432x-14x^2}}}.


{{{dA/dx=432-28x=0}}}

{{{108-7x=0}}}

{{{108=7x}}}

{{{highlight(x=15.43)}}}{{{inches}}}



{{{L=108-4x}}}
{{{L=108-4*15.43}}}
{{{highlight(L=46.29)}}}{{{inches}}}
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