MathDB
Circle and 3-4-5

Source: 2014 AIME I Problem 15

March 14, 2014
trigonometryanalytic geometrygeometrycyclic quadrilateralPythagorean TheoremAIME

Problem Statement

In ABC \triangle ABC , AB=3 AB = 3 , BC=4 BC = 4 , and CA=5 CA = 5 . Circle ω\omega intersects AB\overline{AB} at EE and BB, BC\overline{BC} at BB and DD, and AC\overline{AC} at FF and GG. Given that EF=DFEF=DF and DGEG=34\tfrac{DG}{EG} = \tfrac{3}{4}, length DE=abcDE=\tfrac{a\sqrt{b}}{c}, where aa and cc are relatively prime positive integers, and bb is a positive integer not divisible by the square of any prime. Find a+b+ca+b+c.