document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1120168>Question 1120168</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A city zoo borrowed $2,000,000 at simple annual interest to construct a breeding facility. Some of the money was borrowed at 6%, some at 7%, and some at 10%. Use a system of linear equations to determine how much was borrowed at each rate given that the total annual interest was $144,000 and the amount borrowed at 6% was twice the amount borrowed at 10%. Solve the system of linear equations using matrices.\r<BR>\n" );
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document.write( "WORK I'VE ALREADY DONE (Please advise):<BR>\n" );
document.write( "I've come up with the following equations<BR>\n" );
document.write( "x+y+z=2000000<BR>\n" );
document.write( "0.06x+0.07y+0.10z=144000<BR>\n" );
document.write( "y=4z\r<BR>\n" );
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document.write( "with the following matrix:\r<BR>\n" );
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document.write( "[1,1,1]* [2000000]* [x]<BR>\n" );
document.write( "[0.06, 0.07, 0.10]* [144000]*[y]<BR>\n" );
document.write( "[0,1,-4]*[0]*[z]\r<BR>\n" );
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document.write( "To get the following answers: 500000,1200000,300000\r<BR>\n" );
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document.write( "Please tell me what I'm doing wrong. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #735826 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=735826\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First and second equations look good.<BR>\n" );
document.write( "y is twice z, why do you have the equation with y equal to 4 times z?<BR>\n" );
document.write( "Correct that and find the solution.  </SPAN>\n" );
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