MathDB
Problem: 2004 AMC 10 #22

Source:

February 1, 2007

Problem Statement

Square ABCDABCD has side length 2. A semicircle with diameter ABAB is constructed inside the square, and the tangent to the semicircle from CC intersects side ADAD at EE. What is the length of CECE?
[asy]defaultpen(linewidth(0.8)); pair A=origin, B=(1,0), C=(1,1), D=(0,1), X=tangent(C, (0.5,0), 0.5, 1), F=C+2*dir(C--X), E=intersectionpoint(C--F, A--D); draw(C--D--A--B--C--E); draw(Arc((0.5,0), 0.5, 0, 180)); pair point=(0.5,0.5); label("AA", A, dir(point--A)); label("BB", B, dir(point--B)); label("CC", C, dir(point--C)); label("DD", D, dir(point--D)); label("EE", E, dir(point--E));[/asy]
<spanclass=latexbold>(A)</span>2+52<spanclass=latexbold>(B)</span>5<spanclass=latexbold>(C)</span>6<spanclass=latexbold>(D)</span>52<spanclass=latexbold>(E)</span>55 <span class='latex-bold'>(A)</span>\frac{2+\sqrt5}2\qquad <span class='latex-bold'>(B)</span>\sqrt5\qquad <span class='latex-bold'>(C)</span>\sqrt6\qquad <span class='latex-bold'>(D)</span>\frac52\qquad <span class='latex-bold'>(E)</span>5-\sqrt5