document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=80324>Question 80324</A>: <I><SPAN STYLE=\"word-break: break-all;\"> HELP ASAP!!!! An object is propelled vertically upward from the top of a 112-foot building. The quadratic function s(t) = -16t^2 + 176t + 112 models the ball&#8217;s height above the ground, s(t) in feet, t seconds after it was thrown. How many seconds does it take until the object finally hits the ground? Round to the nearest tenth of a second if necessary. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #57641 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=57641\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the object hits the ground when the height s equals zero ... so set s=0 and solve for t\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2%2B176t%2B112=0 ALIGN=MIDDLE  ALT=\"-16t%5E2%2B176t%2B112=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > .. dividing by -16 gives <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5E2-11t-7=0 ALIGN=MIDDLE  ALT=\"t%5E2-11t-7=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > .. no integer factors\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "using quadratic equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=%2811+%2B-+sqrt%28%28-11%29%5E2-4%2A1%2A%28-7%29%29%29%2F%282%2A1%29 ALIGN=MIDDLE  ALT=\"t=%2811+%2B-+sqrt%28%28-11%29%5E2-4%2A1%2A%28-7%29%29%29%2F%282%2A1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=%2811+%2B-+sqrt%28149%29%29%2F2 ALIGN=MIDDLE  ALT=\"t=%2811+%2B-+sqrt%28149%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > ... t=-.6 and t=11.6 , negative value is not realistic   </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );