document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1158349>Question 1158349</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The function I(t) = -0.11 + 1.6t represents the yearly income (or loss) from real estate investment, where t is time in years. After what year does income begin to decline? Round the answer to the nearest tenth. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #781280 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=781280\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The function I(t) = -0.11 + 1.6t represents the yearly income=> I have noticed you have linear equation; there is no certain point where a line decline\r<BR>\n" );
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document.write( "I assume you have:\r<BR>\n" );
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document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+-0.1t%5E2+%2B+1.6t+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+-0.1t%5E2+%2B+1.6t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > which is a parabola that have a maximum at vertex\r<BR>\n" );
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document.write( "so, write equation in vertex form: \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+%28-0.1t%5E2+%2B+1.6t%29+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+%28-0.1t%5E2+%2B+1.6t%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >....factor out <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-0.1 ALIGN=MIDDLE  ALT=\"-0.1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+-0.1%28t%5E2-+16t%29+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+-0.1%28t%5E2-+16t%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >........complete square\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+-0.1%28t%5E2-+16t%2Bb%5E2%29-%28-0.1%29b%5E2+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+-0.1%28t%5E2-+16t%2Bb%5E2%29-%28-0.1%29b%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >.....<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b=16%2F2=8 ALIGN=MIDDLE  ALT=\"b=16%2F2=8\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+-0.1%28t%5E2-+16t%2B8%5E2%29%2B0.1%2A8%5E2+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+-0.1%28t%5E2-+16t%2B8%5E2%29%2B0.1%2A8%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+-0.1%28t-+8%29%5E2%2B0.1%2A64+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+-0.1%28t-+8%29%5E2%2B0.1%2A64+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I%28t%29+=+-0.1%28t-+8%29%5E2%2B6.4+ ALIGN=MIDDLE  ALT=\"I%28t%29+=+-0.1%28t-+8%29%5E2%2B6.4+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "=> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=8 ALIGN=MIDDLE  ALT=\"h=8\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=6.4 ALIGN=MIDDLE  ALT=\"k=6.4\"   DISABLED_style= \"max-width:90%; height:auto;\" >=> vertex is at (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8 ALIGN=MIDDLE  ALT=\"8\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6.4 ALIGN=MIDDLE  ALT=\"6.4\"   DISABLED_style= \"max-width:90%; height:auto;\" >)\r<BR>\n" );
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document.write( "a maximum will be at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8 ALIGN=MIDDLE  ALT=\"8\"   DISABLED_style= \"max-width:90%; height:auto;\" > years, and after <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8 ALIGN=MIDDLE  ALT=\"8\"   DISABLED_style= \"max-width:90%; height:auto;\" > years income will begin to decline\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing+%28+600%2C+600%2C+-10%2C+15%2C+-10%2C+15%2C+%0D%0Acircle%288%2C6.4%2C.12%29%2Clocate%288%2C6.4%2CV%288%2C6.4%29%29%2C%0D%0Agraph%28+600%2C+600%2C+-10%2C+15%2C+-10%2C+15%2C+-0.1%28x-+8%29%5E2%2B6.4%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( " </SPAN>\n" );
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