document.write( "Question 57310This question is from textbook Elementary and Intermediate algebra
\n" ); document.write( ": Your assistance is greatly appreciated. \r
\n" ); document.write( "\n" ); document.write( "Angela needs 20 quarts of 50% antifreeze solution in her radiator. She plans to obtain this by mixing some pure antifreeze with an appropriate amount of 40% antifreeze solution. How many quarts of each should she use? \n" ); document.write( "
Algebra.Com's Answer #39019 by CrazyMan Jr.(21)\"\" \"About 
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0.4x+1x = 0.5
\n" ); document.write( "x+y = 20
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\n" ); document.write( "0.4x+1y = 0.5 0.6y = -7.5 y = -12.5
\n" ); document.write( "0.4x+0.4y = 8 0.6y/0.6 = -7.5/0.6\r
\n" ); document.write( "\n" ); document.write( "Sub In\r
\n" ); document.write( "\n" ); document.write( "0.4x+1(-12.5) = 0.5
\n" ); document.write( "0.4x(+-)12.5 = 0.5
\n" ); document.write( "0.4x-12.5(+12.5) = 0.5(+12.5)
\n" ); document.write( "0.4x = 13
\n" ); document.write( "0.4x/0.4 = 13/0.4
\n" ); document.write( "x = 32.5\r
\n" ); document.write( "\n" ); document.write( "Proof - Sub In Again\r
\n" ); document.write( "\n" ); document.write( "0.4(32.5)+1(-12.5) = 0.5
\n" ); document.write( "13+-12.5 = 0.5
\n" ); document.write( "0.5 = 0.5\r
\n" ); document.write( "\n" ); document.write( "N.P.
\n" ); document.write( "J-Man \n" ); document.write( "
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