MathDB
Max Inscribed Equilateral Triangle

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December 20, 2005
geometryrectanglealgebrapolynomialAMCAIMEtrigonometry

Problem Statement

The sides of rectangle ABCDABCD have lengths 10 and 11. An equilateral triangle is drawn so that no point of the triangle lies outside ABCD.ABCD. The maximum possible area of such a triangle can be written in the form pqr,p\sqrt{q}-r, where p,q,p, q, and rr are positive integers, and qq is not divisible by the square of any prime number. Find p+q+r.p+q+r.