document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=984228>Question 984228</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a ball is thrown into the air at a speed of 115ft/sec from an initial height of 6ft off the ground. How long will it take the ball to hit the ground?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #604999 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=604999\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is a parabola with equation y=-16t^2+115t+6<BR>\n" );
document.write( "When t=0, the ball is 6 feet off the ground.<BR>\n" );
document.write( "Solve for t, and one of the roots should be slightly negative.\r<BR>\n" );
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document.write( "y=0 when the ball is on the ground.\r<BR>\n" );
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document.write( "quadratic formula<BR>\n" );
document.write( "-(1/32)(-115 +/- sqrt (115^2+384)   ;;; that is sqrt (13225+384)= sqrt (13993)=116.65\r<BR>\n" );
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document.write( "-(1/32) (-115-116.65)=7.24 sec  ANSWER<BR>\n" );
document.write( "the negative root is -(1/32)(-115+116.65)= -0.05 sec\r<BR>\n" );
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