document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=539307>Question 539307</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A man wants to blend 30kg of coffee and each kilo cost $4.80.<BR>\n" );
document.write( "One brand of coffee cost $6 dollars and $4 dollars for a kilo. How<BR>\n" );
document.write( "much kilos of each brand of coffee should be used? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #353401 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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/cgi-bin/show-face.mpl?user=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=353401\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a ALIGN=MIDDLE  ALT=\"a\"   DISABLED_style= \"max-width:90%; height:auto;\" > = kg of $6/kg coffee needed<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b ALIGN=MIDDLE  ALT=\"b\"   DISABLED_style= \"max-width:90%; height:auto;\" > = kg of $4/kg coffee needed<BR>\n" );
document.write( "given:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+6a+ ALIGN=MIDDLE  ALT=\"+6a+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = cost of $6 coffee<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4b+ ALIGN=MIDDLE  ALT=\"+4b+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = cost of $4 coffee<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+%2B+b+=+30+ ALIGN=MIDDLE  ALT=\"+a+%2B+b+=+30+\"   DISABLED_style= \"max-width:90%; height:auto;\" > kg<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+6a+%2B+4b+%29%2F+30+=+4.8+ ALIGN=MIDDLE  ALT=\"+%28+6a+%2B+4b+%29%2F+30+=+4.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" > dollars<BR>\n" );
document.write( "-------------------------<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+6a+%2B+4b+=+144+ ALIGN=MIDDLE  ALT=\"+6a+%2B+4b+=+144+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3a+%2B+2b+=+72+ ALIGN=MIDDLE  ALT=\"+3a+%2B+2b+=+72+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sides of (1) by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2 ALIGN=MIDDLE  ALT=\"2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and<BR>\n" );
document.write( "subtract (1) from (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3a+%2B+2b+=+72+ ALIGN=MIDDLE  ALT=\"+3a+%2B+2b+=+72+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+-2a+-+2b+=+-60+ ALIGN=MIDDLE  ALT=\"+-2a+-+2b+=+-60+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+=+12+ ALIGN=MIDDLE  ALT=\"+a+=+12+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and, since<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+a+%2B+b+=+30+ ALIGN=MIDDLE  ALT=\"+a+%2B+b+=+30+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+b+=+18+ ALIGN=MIDDLE  ALT=\"+b+=+18+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "12 kg of $6/kg coffee are needed<BR>\n" );
document.write( "18 kg of $4/kg coffee are needed<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+6a+%2B+4b+%29%2F+30+=+4.8+ ALIGN=MIDDLE  ALT=\"+%28+6a+%2B+4b+%29%2F+30+=+4.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+6%2A12+%2B+4%2A18+%29%2F+30+=+4.8+ ALIGN=MIDDLE  ALT=\"+%28+6%2A12+%2B+4%2A18+%29%2F+30+=+4.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+72+%2B+72+%29+%2F+30+=+4.8+ ALIGN=MIDDLE  ALT=\"+%28+72+%2B+72+%29+%2F+30+=+4.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+144+=+4.8%2A30+ ALIGN=MIDDLE  ALT=\"+144+=+4.8%2A30+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+144+=+144+ ALIGN=MIDDLE  ALT=\"+144+=+144+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );