document.write( "Question 1000909: How many gallons of a 30% hydrochloric acid solution and 80% hydrochloric acid solution must be mixed to get 20 gallons of a 50% hydrochloric acid solution.
\n" ); document.write( "so far i have tried these two equations and than substituted:
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\n" ); document.write( "30x+80y=50
\n" ); document.write( "x+y=20
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\n" ); document.write( "and \r
\n" ); document.write( "\n" ); document.write( ".3x+.8y=.5
\n" ); document.write( "x+y=20\r
\n" ); document.write( "\n" ); document.write( "every time the answer end being (x=31,y=-11) as far as i see you cannot have a negative amount of the 80% solution. help... \n" ); document.write( "
Algebra.Com's Answer #618225 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "You are forgetting to multiply the 50% or .5 by the 20 gallons \r\n" );
document.write( "and you are only putting .5 instead of .5(20)\r\n" );
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document.write( "That is, you have this:\r\n" );
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document.write( ".3x+.8y=.5\r\n" );
document.write( "x+y=20 \r\n" );
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document.write( "but you should have this:\r\n" );
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document.write( ".3x+.8y=.5(20)\r\n" );
document.write( "x+y=20 \r\n" );
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document.write( "Now try it.\r\n" );
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document.write( "Edwin
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