document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1158307>Question 1158307</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown vertically upward from the ground. Its distance in feet from the ground in t seconds is s=-16t+224t. After how many seconds will the ball be 720 feet from the​ ground?\r<BR>\n" );
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document.write( "please help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #781220 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=781220\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Note, I am assuming you meant s=-16t^2+224t\r<BR>\n" );
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document.write( "720=-16t^2+224t<BR>\n" );
document.write( "16t^2-224t+720=0<BR>\n" );
document.write( "divide by 16<BR>\n" );
document.write( "t^2-14t+45=0<BR>\n" );
document.write( "(t-9)(t-5)=0<BR>\n" );
document.write( "when t= 5 and 9 seconds\r<BR>\n" );
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