document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=970359>Question 970359</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hugh Betcha launched a model rocket with an initial speed of 88 feet per second. After how many seconds will the rocket be 40 feet high? Note: The approximate height h (in feet) is modeled by: h=-16t^2+vt, where t is the time in motion (in seconds) and v is the initial upward velocity (in feet per second).  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #593026 by </B><A HREF=/tutors/aboutme.mpl?userid=amarjeeth123><B>amarjeeth123(569)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=amarjeeth123><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=593026\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Substituting the initial velocity we get,<BR>\n" );
document.write( "h=-16t^2+88t<BR>\n" );
document.write( "For 40 feet we have,<BR>\n" );
document.write( "40=-16t^2+88t<BR>\n" );
document.write( "16t^2-88t+40=0<BR>\n" );
document.write( "2t^2-11t+5=0<BR>\n" );
document.write( "2t^2-10t-t+5=0<BR>\n" );
document.write( "2t(t-5)-1(t-5)=0<BR>\n" );
document.write( "(2t-1)(t-5)=0<BR>\n" );
document.write( "t=5 sec.<BR>\n" );
document.write( "At t=5 sec the rocket is at 40 feet from the ground. </SPAN>\n" );
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