document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=607388>Question 607388</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How much of a 40% antifreeze solution must a mechanic mix with an 80% antifreeze solution if 20 gallons of a 50% antifreeze solution are needed?\r<BR>\n" );
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document.write( "Here's what I tried:\r<BR>\n" );
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document.write( "Let x= amount of 40%, y= amount of 80%\r<BR>\n" );
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document.write( "0.40x + 0.80y = 0.5(20)<BR>\n" );
document.write( "x     +     y = 20\r<BR>\n" );
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document.write( "Multiplied by 10 to get rid of decimals in first equation:\r<BR>\n" );
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document.write( "4x + 8y = 10<BR>\n" );
document.write( "x  +  y = 20\r<BR>\n" );
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document.write( "Put into matrices and got:\r<BR>\n" );
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document.write( "(37.5, -17.5)\r<BR>\n" );
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document.write( "The answer is supposed to equal to 15 gal of 40%, 5 gal of 80% according to the lab worksheet I'm working on. I don't know what I am doing wrong. </SPAN>\n" );
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document.write( "Hi<BR>\n" );
document.write( "Let x= amount of 40%, y= amount of 80% <BR>\n" );
document.write( "0.40x + 0.80y = 0.5(20)<BR>\n" );
document.write( " x + y = 20 OR x = 20-y<BR>\n" );
document.write( "good Work! substituting (20-y) for x<BR>\n" );
document.write( "0.40(20-y) + 0.80y = 0.5(20)<BR>\n" );
document.write( "  .40y = .5(20)-.40(20)<BR>\n" );
document.write( "     y = .10(20)/.40<BR>\n" );
document.write( "     y = 5 gal of the 80% solution and 15gal of the 40% solution (5 + 15 = 20) </SPAN>\n" );
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