document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=801838>Question 801838</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 100 gallons of a 75% glycerin solution is made up by conbinding a 30% glycerin soulition with a 90% glycerin solution, how many gallons of each a solution must be used?? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #483656 by </B><A HREF=/tutors/aboutme.mpl?userid=wilft1><B>wilft1(217)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=wilft1><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=wilft1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=483656\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> this will use 2 equations, solved using the addition method\r<BR>\n" );
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document.write( "x + y = 100<BR>\n" );
document.write( "30x + 90y = 75\r<BR>\n" );
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document.write( "start by multiplying 100 x 75 and putting the answer in the bottom equation...\r<BR>\n" );
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document.write( "x + y = 100<BR>\n" );
document.write( "30x + 90y = 7500\r<BR>\n" );
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document.write( "now, time to get rid of one of the variables, lets get rid of x by multiplying the top line by -30 and adding the two lines together...\r<BR>\n" );
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document.write( "-30x - 30y = -3000<BR>\n" );
document.write( "30x + 90y  = 7500<BR>\n" );
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document.write( "60y = 4500\r<BR>\n" );
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document.write( "divide both sides by 60\r<BR>\n" );
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document.write( "y = 75\r<BR>\n" );
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document.write( "now we know the value for y, lets plug that number into the original equation to find the value of x\r<BR>\n" );
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document.write( "30x + 90(75) = 7500\r<BR>\n" );
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document.write( "30x + 6750 = 7500\r<BR>\n" );
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document.write( "subtract 6750 from both sides\r<BR>\n" );
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document.write( "30x = 750\r<BR>\n" );
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document.write( "divide both sides by 30\r<BR>\n" );
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document.write( "x = 25\r<BR>\n" );
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document.write( "so now we know, 25 gallons of 30% solution and 75 gallons of 90% solution. </SPAN>\n" );
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