document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=87764>Question 87764</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0073022446/algebrahomeworkh>Intermediate Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> The quadratic function that models the fireworks’ height s(x) in feet x seconds after they are launched is given by the equation s(x) = -16x^2+200x + 4.  When should the fireworks explode so that they go off at the greatest height?  What is that height? [Hint:  Find the vertex of the quadratic function s(x).]  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #63649 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=63649\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The vertex of the parabola <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+ax%5E2+%2Bbx+%2Bc ALIGN=MIDDLE  ALT=\"y+=+ax%5E2+%2Bbx+%2Bc\"   DISABLED_style= \"max-width:90%; height:auto;\" > occurs at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-b%2F%282a%29+ ALIGN=MIDDLE  ALT=\"x=-b%2F%282a%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > .\r<BR>\n" );
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document.write( "Therefore, for your function <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%28x%29+=+-16x%5E2%2B200x+%2B+4 ALIGN=MIDDLE  ALT=\"s%28x%29+=+-16x%5E2%2B200x+%2B+4\"   DISABLED_style= \"max-width:90%; height:auto;\" >, the vertex occurs at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=+-200%2F%282%28-16%29+%29=+-200%2F-32=25%2F5+=+6.25+ ALIGN=MIDDLE  ALT=\"x=+-200%2F%282%28-16%29+%29=+-200%2F-32=25%2F5+=+6.25+\"   DISABLED_style= \"max-width:90%; height:auto;\" > seconds.\r<BR>\n" );
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document.write( "The maximum height is at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=s%286.25%29+=+629+ ALIGN=MIDDLE  ALT=\"s%286.25%29+=+629+\"   DISABLED_style= \"max-width:90%; height:auto;\" > feet.  By the way, I used a graphing calculator, with window:  x= [-2,14], y = [-100, 700].  It looks like this:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28+300%2C+600%2C+-2%2C14%2C-100%2C700%2C+-16x%5E2%2B200x+%2B+4%29+ ALIGN=MIDDLE  ALT=\"graph%28+300%2C+600%2C+-2%2C14%2C-100%2C700%2C+-16x%5E2%2B200x+%2B+4%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "R^2  Retired from SCC<BR>\n" );
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