MathDB
Math Prize 2013 Problem 7

Source:

September 10, 2013
analytic geometrygeometrygeometric transformationrotationtrigonometrytrig identitiesLaw of Sines

Problem Statement

In the figure below, ABC\triangle ABC is an equilateral triangle. [asy] import graph; unitsize(60); axes("xx", "yy", (0, 0), (1.5, 1.5), EndArrow); real w = sqrt(3) - 1; pair A = (1, 1); pair B = (0, w); pair C = (w, 0); draw(A -- B -- C -- cycle); dot(Label("A(1,1)A(1, 1)", A, NE), A); dot(Label("BB", B, W), B); dot(Label("CC", C, S), C); [/asy] Point AA has coordinates (1,1)(1, 1), point BB is on the positive yy-axis, and point CC is on the positive xx-axis. What is the area of ABC\triangle ABC?