document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=44144>Question 44144</A>: <I><SPAN STYLE=\"word-break: break-all;\"> h=-16t^2+48t+160\r<BR>\n" );
document.write( "\n" );
document.write( "how many seconds til it hits 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 #29077 by </B><A HREF=/tutors/aboutme.mpl?userid=adamchapman><B>adamchapman(301)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=adamchapman><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=29077\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> h= height<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=-16t%5E2%2B48t%2B160 ALIGN=MIDDLE  ALT=\"h=-16t%5E2%2B48t%2B160\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "when it hits the ground, h=0. So:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2%2B48t%2B160=0 ALIGN=MIDDLE  ALT=\"-16t%5E2%2B48t%2B160=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Use the quadratic solver <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "where<BR>\n" );
document.write( "a=-16<BR>\n" );
document.write( "b=48<BR>\n" );
document.write( "c=160<BR>\n" );
document.write( "Now: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-48+%2B-+sqrt%28+48%5E2-4%2A%28-16%29%2A160+%29%29%2F%282%2A%28-16%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-48+%2B-+sqrt%28+48%5E2-4%2A%28-16%29%2A160+%29%29%2F%282%2A%28-16%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-48+%2B-+sqrt%28+2304%2B10240%29%29%2F-32+ ALIGN=MIDDLE  ALT=\"t+=+%28-48+%2B-+sqrt%28+2304%2B10240%29%29%2F-32+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-48+%2B-+sqrt%28+12544%29%29%2F-32+ ALIGN=MIDDLE  ALT=\"t+=+%28-48+%2B-+sqrt%28+12544%29%29%2F-32+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+1.5+%2B-+112%2F-32+ ALIGN=MIDDLE  ALT=\"t+=+1.5+%2B-+112%2F-32+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+1.5+%2B-+3.5+ ALIGN=MIDDLE  ALT=\"t+=+1.5+%2B-+3.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So t=-2 or t=5<BR>\n" );
document.write( "t=-2 would mean going back in time, which i think is impossible, so th must be 5 seconds.<BR>\n" );
document.write( "I have graphed heigt with time below. This should confirm that h=0 when t=5.\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+200%2C+0%2C+6%2C+-1%2C+200%2C+-16x%5E2%2B48x%2B160%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+200%2C+0%2C+6%2C+-1%2C+200%2C+-16x%5E2%2B48x%2B160%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
document.write( "\n" );
document.write( "I hope this helps <BR>\n" );
document.write( "P.S. I am trying to start up my own homework help website. I would be extremely grateful if you would e-mail me some feedback on the help you received to adam.chapman@student.manchester.ac.uk  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );