Assign to each side
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of a convex polygon
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the maximum area of a triangle that has
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as a side and is contained in
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. Show that the sum of the areas assigned to the sides of
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is at least twice the area of
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.
%V0
Assign to each side $b$ of a convex polygon $P$ the maximum area of a triangle that has $b$ as a side and is contained in $P$. Show that the sum of the areas assigned to the sides of $P$ is at least twice the area of $P$.