document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=70>Question 70</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A baseball is hit by a batter.  The function <BR>\n" );
document.write( "s(t) = -16t to the second power + 140t + 3 <BR>\n" );
document.write( "models the ball's height above the ground, s(t) in feet t seconds after it was hit.  How long will it take for the ball to strike the ground?  Round to the nearest tenth of a second. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #31 by </B><A HREF=/tutors/aboutme.mpl?userid=ichudov><B>ichudov(507)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ichudov><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=ichudov><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=31\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The ball strikes the ground when s(t) is equal to zero, since hitting the ground is equivalent to saying that the ball is at zero height.\r<BR>\n" );
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document.write( "So, we have a problem: find t such that s(t) = 0. \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2%2B140t%2B3+=+0 ALIGN=MIDDLE  ALT=\"-16t%5E2%2B140t%2B3+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solve it with my <A  rel=nofollow HREF=/algebra/homework/quadratic/>quadratic solver</A>. </SPAN>\n" );
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