document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1043568>Question 1043568</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, I'm trying to write an equation to solve this problem and running into difficulty:\r<BR>\n" );
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document.write( "I have 300000 to invest. A safe investment earns 3.5% per year. A risky investment yields 7% a year. How much is needed to be invested at each rate to earn $15,000 per year. \r<BR>\n" );
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document.write( "I'm certain it has something to do with the simple interest formula but I just can't make this work. I get that SI=prt, but I can't work out beyond that.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #658714 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=658714\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (How many years?)  The wording implies just 1 year.\r<BR>\n" );
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document.write( "The description works like a mixture problem.\r<BR>\n" );
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document.write( "x amount for risky<BR>\n" );
document.write( "y amount for safe<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28x%2By=300000%2C0.07x%2B0.035y=15000%29 ALIGN=MIDDLE  ALT=\"system%28x%2By=300000%2C0.07x%2B0.035y=15000%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "STEPS<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7x%2B3.5y=1500000 ALIGN=MIDDLE  ALT=\"7x%2B3.5y=1500000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=300000-x ALIGN=MIDDLE  ALT=\"y=300000-x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7x%2B3.5%28300000-x%29=1500000 ALIGN=MIDDLE  ALT=\"7x%2B3.5%28300000-x%29=1500000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7x%2B1050000-3.5x=1500000 ALIGN=MIDDLE  ALT=\"7x%2B1050000-3.5x=1500000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3.5x%2B1050000=1500000 ALIGN=MIDDLE  ALT=\"3.5x%2B1050000=1500000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3.5x=450000 ALIGN=MIDDLE  ALT=\"3.5x=450000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28system%28x=128571%2Cy=171429%29%29 ALIGN=MIDDLE  ALT=\"highlight%28system%28x=128571%2Cy=171429%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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