April 29–May 5, 2008

Problem

Let ABCD be a unit square. Suppose E is a point on AB and F is a point on AD so that the triangle AEF has perimeter 2. Find angle ECF.

(digram)

Solution

here.

List of solvers

Steve Wilmarth (undergrad); Jacob Lewis, Doug Faust, Dustin Moody (graduate); Konrad Schroder (staff); Lloyd Sakazaki, Stefan Sharkansky, Kevin Lo, Kate Smith (outside).

Stefan Sharkansky wins the prize!