MathDB
Quadrilateral area

Source: AHSME 1991 problem 23

October 30, 2011
geometryratioAMC

Problem Statement

If ABCDABCD is a 2 X 22\ X\ 2 square, EE is the midpoint of AB\overline{AB}, FF is the midpoint of BC\overline{BC}, AF\overline{AF} and DE\overline{DE} intersect at II, and BD\overline{BD} and AF\overline{AF} intersect at HH, then the area of quadrilateral BEIHBEIH is
[asy] size(200); defaultpen(linewidth(0.7)+fontsize(10)); pair B=origin, A=(0,2), C=(2,0), D=(2,2), E=(0,1), F=(1,0); draw(A--E--B--F--C--D--A--F^^E--D--B); label("A", A, NW); label("B", B, SW); label("C", C, SE); label("D", D, NE); label("E", E, W); label("F", F, S); label("H", (.8,0.6)); label("I", (0.4,1.4)); [/asy]
<spanclass=latexbold>(A)</span> 13<spanclass=latexbold>(B)</span> 25<spanclass=latexbold>(C)</span> 715<spanclass=latexbold>(D)</span> 815<spanclass=latexbold>(E)</span> 35 <span class='latex-bold'>(A)</span>\ \frac{1}{3}\qquad<span class='latex-bold'>(B)</span>\ \frac{2}{5}\qquad<span class='latex-bold'>(C)</span>\ \frac{7}{15}\qquad<span class='latex-bold'>(D)</span>\ \frac{8}{15}\qquad<span class='latex-bold'>(E)</span>\ \frac{3}{5}