So inside every triangle there is a very special circle, sort of in prison there. It is called the inscribed circle. Study of this circle provides one of the beginnings to what is, in the business world, the task if packing things efficiently. A good question would be: for a circle of a given size, is there a triangle that can enclose it with less material (perimeter, or sum of the side lengths) than a square would, or could, use?
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