document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=57310>Question 57310</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0072538953/algebrahomeworkh>Elementary and Intermediate algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Your assistance is greatly appreciated.  \r<BR>\n" );
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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? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #39017 by </B><A HREF=/tutors/aboutme.mpl?userid=aaaaaaaa><B>aaaaaaaa(138)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=aaaaaaaa><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=39017\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> p = quarts of pure antifreeze sol.<BR>\n" );
document.write( "i = quarts of the impure one\r<BR>\n" );
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document.write( "The second equation needs some explanation, 50% of 20 is 10.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28p+%2B+i+=+20%2C+p+%2B+0.4i+=+10%29 ALIGN=MIDDLE  ALT=\"system%28p+%2B+i+=+20%2C+p+%2B+0.4i+=+10%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=linear_substitution.solver>SOLVE linear system by SUBSTITUTION</A></TD></TR>\n" );
document.write( "<TR><TD  ALIGN=LEFT>Solve:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+system%28+%0D%0A++++1%5Cp+%2B+1%5Ci+=+20%2C%0D%0A++++1%5Cp+%2B+0.4%5Ci+=+10+%29%0D%0A++ ALIGN=MIDDLE  ALT=\"+system%28+%0D%0A++++1%5Cp+%2B+1%5Ci+=+20%2C%0D%0A++++1%5Cp+%2B+0.4%5Ci+=+10+%29%0D%0A++\"   DISABLED_style= \"max-width:90%; height:auto;\" >We'll use substitution. After moving 1*i to the right, we get:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Ap+=+20+-+1%2Ai ALIGN=MIDDLE  ALT=\"1%2Ap+=+20+-+1%2Ai\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p+=+20%2F1+-+1%2Ai%2F1 ALIGN=MIDDLE  ALT=\"p+=+20%2F1+-+1%2Ai%2F1\"   DISABLED_style= \"max-width:90%; height:auto;\" >. Substitute that<BR>\n" );
document.write( "  into another equation:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2A%2820%2F1+-+1%2Ai%2F1%29+%2B+0.4%5Ci+=+10 ALIGN=MIDDLE  ALT=\"1%2A%2820%2F1+-+1%2Ai%2F1%29+%2B+0.4%5Ci+=+10\"   DISABLED_style= \"max-width:90%; height:auto;\" > and simplify: So, we know that i=16.6666666666667. Since <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p+=+20%2F1+-+1%2Ai%2F1 ALIGN=MIDDLE  ALT=\"p+=+20%2F1+-+1%2Ai%2F1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, p=3.3333333333333.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Answer: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28+p=3.3333333333333%2C+i=16.6666666666667+%29 ALIGN=MIDDLE  ALT=\"system%28+p=3.3333333333333%2C+i=16.6666666666667+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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