document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1036883>Question 1036883</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rocket is fired directly upwards with a velocity of  160 ft/sec, from a platform which is 9 feet above the ground.  The equation for the rocket's height,  H , as a function of time,  t , is given by the function \r<BR>\n" );
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document.write( "H(t)= -16t^2+160t+9\r<BR>\n" );
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document.write( "Find the maximum height of the rocket. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #651586 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=651586\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The t value is the vertex, which is -b/2a<BR>\n" );
document.write( "That is -160/-32, or 5.<BR>\n" );
document.write( "At 5 seconds, it is at maximum height.  That is -16(25)+160(5)+9=409 feet.<BR>\n" );
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