Question 1185479
Width 2L-4
Length L
120, the area


{{{L(2L-4)=120}}}
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{{{L(L-2)=60}}}---------------{{{60=4*15=5*12=6*10}}}


{{{L^2-2L-60=0}}}

{{{L=(2+- sqrt(4+4*60))/2}}}

{{{L=(2+- 2sqrt(61))/2}}}

{{{highlight_green(L=1+sqrt(61))}}}



{{{(L)^2+(2L-4)^2=d^2}}}

{{{d=sqrt(L^2+4L^2-16L+16)}}}

{{{highlight_green(d=sqrt(5L^2-16L+16))}}}---------substitute here for L and evaluate d.


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