MathDB
1987 AMC 12 #21 - Square Inscribed in Triangle

Source:

January 1, 2012
geometryAMC

Problem Statement

There are two natural ways to inscribe a square in a given isosceles right triangle. If it is done as in Figure 1 below, then one finds that the area of the square is 441cm2441 \text{cm}^2. What is the area (in cm2\text{cm}^2) of the square inscribed in the same ABC\triangle ABC as shown in Figure 2 below? [asy] draw((0,0)--(10,0)--(0,10)--cycle); draw((-25,0)--(-15,0)--(-25,10)--cycle); draw((-20,0)--(-20,5)--(-25,5)); draw((6.5,3.25)--(3.25,0)--(0,3.25)--(3.25,6.5)); label("A", (-25,10), W); label("B", (-25,0), W); label("C", (-15,0), E); label("Figure 1", (-20, -5)); label("Figure 2", (5, -5)); label("A", (0,10), W); label("B", (0,0), W); label("C", (10,0), E); [/asy] <spanclass=latexbold>(A)</span> 378<spanclass=latexbold>(B)</span> 392<spanclass=latexbold>(C)</span> 400<spanclass=latexbold>(D)</span> 441<spanclass=latexbold>(E)</span> 484 <span class='latex-bold'>(A)</span>\ 378 \qquad<span class='latex-bold'>(B)</span>\ 392 \qquad<span class='latex-bold'>(C)</span>\ 400 \qquad<span class='latex-bold'>(D)</span>\ 441 \qquad<span class='latex-bold'>(E)</span>\ 484