document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=121302>Question 121302</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Science and medicine:<BR>\n" );
document.write( "A ball is thrown upward from the roof of a building 100m tall width the initial velocity of 20 m/s. When will the ball reach the height of 80 m?\r<BR>\n" );
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document.write( "I would really appreciate some help on this, Thank you very much. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #89011 by </B><A HREF=/tutors/aboutme.mpl?userid=Nate><B>Nate(3500)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Nate><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=89011\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> h(t) = -16t^2 + 20t + 100<BR>\n" );
document.write( "80 = -16t^2 + 20t + 100<BR>\n" );
document.write( "0 = -16t^2 + 20t + 20<BR>\n" );
document.write( "0 = -4t^2 + 5t + 5<BR>\n" );
document.write( "t = ( -5 +- sqrt( 25 + 4*4*5 ) ) / (-2*4)<BR>\n" );
document.write( "t = ( 5 +- sqrt( 105 ) ) / 8 </SPAN>\n" );
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