Problem 4 (2001 AIME I)
AIME IMedium
From module Law of Sines
Problem
In triangle ABC, angles A and B measure 60° and 80°, respectively. The bisector of angle C intersects AB at D, and AD = 1. The area of triangle ABC can be written in the form (a√b)/c, where a, b, and c are positive integers, and b is not divisible by the square of any prime. Find a + b + c.