document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=556643>Question 556643</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me!  I think that the answer is 5 seconds, but I don't know.  Please show work  :)  \"An object is thrown upward from the top of a 160-foot building with an initial velocity of 48 feet per second. The height h of the object after t seconds is given by the quadratic equation  h =16tē + 48t + 160. When will the object hit the ground?\"\r<BR>\n" );
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document.write( "Thank you in advance for your help!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #362199 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=362199\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  \"An object is thrown upward from the top of a 160-foot building with an initial velocity of 48 feet per second. The height h of the object after t seconds is given by the quadratic equation  h =16tē + 48t + 160. When will the object hit the ground?\"\r<BR>\n" );
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document.write( "At 5 seconds, h = 16*25 + 48*5 + 160<BR>\n" );
document.write( "h(5) = 800 feet<BR>\n" );
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document.write( "h = 0 when it hits the ground.<BR>\n" );
document.write( "h =16tē + 48t + 160 = 0<BR>\n" );
document.write( "solve for t<BR>\n" );
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document.write( "h increases with t, the object will never hit the ground.<BR>\n" );
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