document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=120538>Question 120538</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mike invested $6000 for one year.  He invested part of it at 9% and the rest at 11%.  At the end of the year he earned $624 in interest.  How much did he invest at each rate?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #88364 by </B><A HREF=/tutors/aboutme.mpl?userid=tutor_paul><B>tutor_paul(519)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tutor_paul><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=tutor_paul><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=88364\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Set it up as two equations and two unknowns. Let x be the amount invested at 9%, and let y be the amount invested at 11%. Then you can write:<BR>\n" );
document.write( "Eqn #1: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2By=6000 ALIGN=MIDDLE  ALT=\"x%2By=6000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Eqn #2: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%280.09%29%2By%280.11%29=624 ALIGN=MIDDLE  ALT=\"x%280.09%29%2By%280.11%29=624\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Now you have 2 equations and 2 unknowns. Any time you have at least as many equations as you have unknowns, you can solve the problem!<BR>\n" );
document.write( "Solve Eqn #1 for x:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=6000-y ALIGN=MIDDLE  ALT=\"x=6000-y\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute this value of x into Eqn #2:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%286000-y%29%2A0.09%2By%280.11%29=624 ALIGN=MIDDLE  ALT=\"%286000-y%29%2A0.09%2By%280.11%29=624\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Solve for y:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=540-0.09y%2B.11y=624 ALIGN=MIDDLE  ALT=\"540-0.09y%2B.11y=624\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=540%2B.02y=624 ALIGN=MIDDLE  ALT=\"540%2B.02y=624\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0.02y=84 ALIGN=MIDDLE  ALT=\"0.02y=84\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=4200%29 ALIGN=MIDDLE  ALT=\"highlight%28y=4200%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now that you have the answer for y, plug that into Eqn #1 and solve for x:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2B4200=6000 ALIGN=MIDDLE  ALT=\"x%2B4200=6000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=1800%29 ALIGN=MIDDLE  ALT=\"highlight%28x=1800%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You can check these answer by making sure each equation holds true when you plug in these values for x and y.<BR>\n" );
document.write( "====================<BR>\n" );
document.write( "Good Luck,<BR>\n" );
document.write( "tutor_paul@yahoo.com<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );