document.write( "Question 1157175: How many liters each of a 40% antifreeze solution and a 80% antifreeze solution must be mixed to make 8 liters of a 50% antifreeze solution? \n" ); document.write( "

Algebra.Com's Answer #779988 by VFBundy(438) $\"\"$ $\"About$

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Liters of 40% solution = x
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\n" ); document.write( "x + y = 8
\n" ); document.write( "0.40x + 0.80y = 0.50(8)
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\n" ); document.write( "x + y = 8
\n" ); document.write( "0.40x + 0.80y = 4
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\n" ); document.write( "Multiply first equation by -0.80:
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\n" ); document.write( "-0.80 - 0.80y = -6.40
\n" ); document.write( "0.40x + 0.80y = 4
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\n" ); document.write( "Add the equations together:
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\n" ); document.write( "-0.40x = -2.40
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\n" ); document.write( "x = 6
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\n" ); document.write( "Since x = 6, and we know x + y = 8, that means y = 2.
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\n" ); document.write( "Liters of 40% solution = x = 6
\n" ); document.write( "Liters of 80% solution = y = 2 \n" ); document.write( "

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