document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=82301>Question 82301</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 #59033 by </B><A HREF=/tutors/aboutme.mpl?userid=303795><B>303795(602)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=303795><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=59033\">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 it reaches the ground the height will be zero so<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=-16t%5E2%2B64t%2B80 ALIGN=MIDDLE  ALT=\"0=-16t%5E2%2B64t%2B80\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Divide each side of the equation 16 to simplify the numbers involved.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=-t%5E2%2B4t%2B5 ALIGN=MIDDLE  ALT=\"0=-t%5E2%2B4t%2B5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sides of the equation by -1 to eliminate the negative sign in front of the t squared.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=t%5E2-4t-5 ALIGN=MIDDLE  ALT=\"0=t%5E2-4t-5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Factorise the trinomial.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=%28t-5%29%28t%2B1%29 ALIGN=MIDDLE  ALT=\"0=%28t-5%29%28t%2B1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "ie t=5 or t=-1.<BR>\n" );
document.write( "The first answer shows the object hits the ground after 5 seconds and the second shows that it was at ground level 1 second before it was thrown upwards.<BR>\n" );
document.write( "In the context of the problem the 5 second answer must be the solution. </SPAN>\n" );
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