document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136654>Question 136654</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this word problem:\r<BR>\n" );
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document.write( "A ball is projected upward from the ground. Its distance in feet from the ground in t seconds is given by the equation s(t)=-16t^2+128t. At what times will the ball be 100 feet from 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 #100089 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=100089\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> put 100 in for s(t) and solve for t __ 100=-16t^2+128t __ 0=-16t^2+128t-100\r<BR>\n" );
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document.write( "dividing by -4 __ 0=4t^2-32t+25\r<BR>\n" );
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document.write( "use the quadratic formula to find the values of t </SPAN>\n" );
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