document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=58464>Question 58464</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618044302/algebrahomeworkh>Algebra structure and Method</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> a rocket is fired upward with an inital speed of 1960 m/s.  after how many minutes does it hit the ground? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #40046 by </B><A HREF=/tutors/aboutme.mpl?userid=6894><B>6894(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=6894><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=40046\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let t be the time when the rocket hits the ground.<BR>\n" );
document.write( "0=1960t-4.9t^2<BR>\n" );
document.write( "0=4.9t(400-t)<BR>\n" );
document.write( "4.9t=0, t=0 (when the rocket hits the ground)<BR>\n" );
document.write( "400-t=0<BR>\n" );
document.write( "400=t<BR>\n" );
document.write( "the rocket hits the ground after 400 seconds or 6 2/3 min.\r<BR>\n" );
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document.write( "formula used: h=rt-4.9t^2 </SPAN>\n" );
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