MathDB
AMC 8 2005 Problem 13

Source:

July 23, 2011
geometry

Problem Statement

The area of polygon ABCDEF ABCDEF is 52 with AB\equal{}8, BC\equal{}9 and FA\equal{}5. What is DE\plus{}EF? [asy]defaultpen(linewidth(0.8));pair a=(0,9), b=(8,9), c=(8,0), d=(4,0), e=(4,4), f=(0,4); draw(a--b--c--d--e--f--cycle); draw(shift(0,-.25)*a--shift(.25,-.25)*a--shift(.25,0)*a); draw(shift(-.25,0)*b--shift(-.25,-.25)*b--shift(0,-.25)*b); draw(shift(-.25,0)*c--shift(-.25,.25)*c--shift(0,.25)*c); draw(shift(.25,0)*d--shift(.25,.25)*d--shift(0,.25)*d); draw(shift(.25,0)*f--shift(.25,.25)*f--shift(0,.25)*f); label("AA", a, NW); label("BB", b, NE); label("CC", c, SE); label("DD", d, SW); label("EE", e, SW); label("FF", f, SW); label("5", (0,6.5), W); label("8", (4,9), N); label("9", (8, 4.5), E);[/asy]
<spanclass=latexbold>(A)</span> 7<spanclass=latexbold>(B)</span> 8<spanclass=latexbold>(C)</span> 9<spanclass=latexbold>(D)</span> 10<spanclass=latexbold>(E)</span> 11 <span class='latex-bold'>(A)</span>\ 7\qquad<span class='latex-bold'>(B)</span>\ 8\qquad<span class='latex-bold'>(C)</span>\ 9\qquad<span class='latex-bold'>(D)</span>\ 10\qquad<span class='latex-bold'>(E)</span>\ 11