document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=91968>Question 91968</A>: <I><SPAN STYLE=\"word-break: break-all;\">  How can I show the equation use for the solution?<BR>\n" );
document.write( "A coffee merchant has coffee beans that sell for $9 per<BR>\n" );
document.write( "pound and $12 per pound. The two types are to be mixed to create 100 lb of a mixture that will sell for $11.25 per pound. How much of each type of bean should be used in the mixture? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #66793 by </B><A HREF=/tutors/aboutme.mpl?userid=mathispowerful><B>mathispowerful(115)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathispowerful><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=66793\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  \r<BR>\n" );
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document.write( "The idea is that the total worth of coffee will remain unchanged before and after mixture.\r<BR>\n" );
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document.write( "Let x represent the amount of $9-coffee<BR>\n" );
document.write( "    y represent the amount of $12-coffee\r<BR>\n" );
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document.write( "then<BR>\n" );
document.write( " x + y = 100<BR>\n" );
document.write( " 9x +  12y = 11.25 * 100 = 1125\r<BR>\n" );
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document.write( "so we have \r<BR>\n" );
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document.write( "x + y = 100<BR>\n" );
document.write( "9x +  12y = 1125\r<BR>\n" );
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document.write( "multiply -9 on both sides of first equation<BR>\n" );
document.write( "-9x - 9y = -900\r<BR>\n" );
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document.write( "add to second equation\r<BR>\n" );
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document.write( "3y = 225\r<BR>\n" );
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document.write( "y =  75 lbs<BR>\n" );
document.write( "and x = 100 -75 = 25 lbs\r<BR>\n" );
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document.write( "so we need to mix 25 lbs of $9-coffee with 75 lbs of $12-coffee.\r<BR>\n" );
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document.write( "  </SPAN>\n" );
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