document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1156068>Question 1156068</A>: <I><SPAN STYLE=\"word-break: break-all;\"> At a certain time of day, a tree that is x meters tall casts a shadow that is x-21 meters long. If the distance from the top of the tree to the end of the shadow is x+3 meters long, what is the height, \"x\", of the tree? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #778760 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=778760\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Consider as a right triangle with hypotenuse (x+3), and square is x^2+6x+9<BR>\n" );
document.write( "one leg is (x-21) the shadow--square is x^2-42x+441<BR>\n" );
document.write( "the height is and square is x^2<BR>\n" );
document.write( "The last two equal the first<BR>\n" );
document.write( "2x^2-42x+441=x^2+6x+9<BR>\n" );
document.write( "x^2-48x+432=0<BR>\n" );
document.write( "(x-36)(x-12)=0<BR>\n" );
document.write( "x=36 and x=12. The latter doesn't work, because x-21 is negative. <BR>\n" );
document.write( "The tree is 36 feet tall ANSWER<BR>\n" );
document.write( "36^2+15^2=39^2, which is a multiple of 3 of a 5-12-13 right triangle.  </SPAN>\n" );
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