document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=458532>Question 458532</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If an object is propelled upward from a height of s feet at an initial velocity of v feet per second, then its height h after t seconds is given by the equation h=-16t^2+vt+s, where h is in feet. If the object is propelled from a height of 8 feet with an initial velocity of 64 feet per second, its height h is given by the equation h=-16t^2+64t+8.\r<BR>\n" );
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document.write( "After how many seconds is the height 68 feet? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #314633 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel1380><B>jorel1380(3719)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel1380><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=jorel1380><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=314633\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 68=-16t2+64t+8<BR>\n" );
document.write( "16t2-64t+60=0<BR>\n" );
document.write( "4t2-16t+15=0<BR>\n" );
document.write( "(2t-5)(2t-3)=0<BR>\n" );
document.write( "t=5/2 or 3/2<BR>\n" );
document.write( "The object is at 68 feet after 3/2 secs, and returns to 68 feet after another second.. </SPAN>\n" );
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