document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=181708>Question 181708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The question is:<BR>\n" );
document.write( "The number of quadruplet births Q in the United States from 1989 to 1998 can be modeled by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Q=+-0.5t%5E3%2B11.7t%5E2-21.5t%2B218.6 ALIGN=MIDDLE  ALT=\"Q=+-0.5t%5E3%2B11.7t%5E2-21.5t%2B218.6\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where t represents the number of years since 1989. For what values of t does this model no longer give realistic data? Explain your reasoning.\r<BR>\n" );
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document.write( "I tried to figure it out, but I think I was way off. I just substituted t for different numbers, but went in order (2,3,4). I just don't understand how to solve it. Please help me and explain how you got it, so I don't just copy, but I will also understand how to solve it. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #136328 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=136328\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The question is:<BR>\n" );
document.write( "The number of quadruplet births Q in the United States from 1989 to 1998 can be modeled by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Q=+-0.5t%5E3%2B11.7t%5E2-21.5t%2B218.6 ALIGN=MIDDLE  ALT=\"Q=+-0.5t%5E3%2B11.7t%5E2-21.5t%2B218.6\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where t represents the number of years since 1989. For what values of t does this model no longer give realistic data? Explain your reasoning.\r<BR>\n" );
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document.write( " Please help me and explain how you got it, so I don't just copy, but I will also understand how to solve it.<BR>\n" );
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document.write( "Q(t) = -0.5t^3+11.7t^2-21.5t+218.6<BR>\n" );
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document.write( "I graphed the function and found that Q(t) is negative<BR>\n" );
document.write( "for x > 22.351.  And, of course Q(t) is not meaningful<BR>\n" );
document.write( "for t < 0 <BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28400%2C300%2C-5%2C100%2C-300%2C850%2C-0.5x%5E3%2B11.7x%5E2-21.5x%2B218.6%29 ALIGN=MIDDLE  ALT=\"graph%28400%2C300%2C-5%2C100%2C-300%2C850%2C-0.5x%5E3%2B11.7x%5E2-21.5x%2B218.6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "================================================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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