Question 1079274
Perimeter in feet,  {{{(1/4)mile*5280(feet/mile)=1320*feet}}}



x, rectangular dimension capped with each semicircle part
y, rectangular dimension not capped with the semicircle part

radius of each semicircle is  {{{x/2}}}.


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Accounting for perimeter and area and simplifying,

{{{system(pi*x+2y=1320,4xy+pi*x^2=400000)}}}
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Solving for y and substituting, and then simplifying,...
{{{pi*x^2-2640x+40000=0}}}



{{{x=198}}}, diameter of semicircle parts, in feet
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{{{y=349}}}, each straight-way part