MathDB
Triangle and Hexagon

Source: 2013 AIME I Problem 12

March 15, 2013
geometrytrigonometryAMCAIMEnumber theoryrelatively primearea of a triangle

Problem Statement

Let PQR\triangle PQR be a triangle with P=75\angle P = 75^\circ and Q=60\angle Q = 60^\circ. A regular hexagon ABCDEFABCDEF with side length 1 is drawn inside PQR\triangle PQR so that side AB\overline{AB} lies on PQ\overline{PQ}, side CD\overline{CD} lies on QR\overline{QR}, and one of the remaining vertices lies on RP\overline{RP}. There are positive integers aa, bb, cc, and dd such that the area of PQR\triangle PQR can be expressed in the form a+bcd\tfrac{a+b\sqrt c}d, where aa and dd are relatively prime and cc is not divisible by the square of any prime. Find a+b+c+da+b+c+d.