document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=82299>Question 82299</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An object is projected upward from the top of a tower. Its distance in feet above the ground after (t)seconds is given by s(t)= -16t^2+64t+80.  How many seconds will it take to reach ground level? The answer is multiple choice.\r<BR>\n" );
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document.write( "a. 1 second<BR>\n" );
document.write( "b. 4 seconds<BR>\n" );
document.write( "c. 5 seconds<BR>\n" );
document.write( "d. 8 seconds  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #58989 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=58989\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> s(t)= -16t^2+64t+80<BR>\n" );
document.write( "When the ball is at ground-level s = 0.<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "-16t^2+64t+80 = 0<BR>\n" );
document.write( "-16(t^2-4t-5)=0<BR>\n" );
document.write( "t^2-4t-5=0<BR>\n" );
document.write( "(t-5)(t+1)=0<BR>\n" );
document.write( "Positive answer: t=5 seconds<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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