MathDB
Physicsish Aime Problem

Source:

February 20, 2006
AMCAIMEtrigonometryquadraticstrig identitiesLaw of Cosines

Problem Statement

Two skaters, Allie and Billie, are at points AA and BB, respectively, on a flat, frozen lake. The distance between AA and BB is 100100 meters. Allie leaves AA and skates at a speed of 88 meters per second on a straight line that makes a 6060^\circ angle with ABAB. At the same time Allie leaves AA, Billie leaves BB at a speed of 77 meters per second and follows the straight path that produces the earliest possible meeting of the two skaters, given their speeds. How many meters does Allie skate before meeting Billie?
[asy] defaultpen(linewidth(0.8)); draw((100,0)--origin--60*dir(60), EndArrow(5)); label("AA", origin, SW); label("BB", (100,0), SE); label("100100", (50,0), S); label("6060^\circ", (15,0), N);[/asy]