Difference between revisions of "1995 AHSME Problems/Problem 8"

(My first shot at Asy)
(No difference)

Revision as of 11:05, 29 April 2008

Problem

In $\triangle ABC$, $\angle C = 90^\circ, AC = 6$ and $BC = 8$. Points $D$ and $E$ are on $\overline{AB}$ and $\overline{BC}$, respectively, and $\angle BED = 90^\circ$. If $DE = 4$, then $BD =$

$\mathrm{(A) \ 5 } \qquad \mathrm{(B) \ \frac {16}{3} } \qquad \mathrm{(C) \ \frac {20}{3} } \qquad \mathrm{(D) \ \frac {15}{2} } \qquad \mathrm{(E) \ 8 }$

Solution

[asy] size(120); defaultpen(0.7); pair  A = (0,6), B = (8,0), C= (0,0), D = (56/15,3.2), E = (4/3,0), F = (0, 3), G = (38/15,1.6); draw(A--B--E--D--E--B--C--A--B--cycle); label("\(A\)",A,W); label("\(B\)",B,E); label("\(C\)",C,SW); label("\(D\)",D,NE); label("\(E\)",E,S); label("\(6\)",F,W); label("\(4\)",G,NW); [/asy]

Since $\triangle BED$ is similar to $\triangle ABC$, it is a 3-4-5 triangle, and thus $BD=4\cdot \dfrac{4}{3}=\dfrac{16}{3}\Rightarrow \boxed{\mathrm{(B)}}$.

See also