document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=449709>Question 449709</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if an object is projected upward with an initial velocity off 64 ft per sec from a height of 336 feet then its height t sec after it is projected is defined by the equation h= -16t^2 + 64 t + 336.  how many sec after it is projected will it hit the ground? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #309373 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=309373\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if an object is projected upward with an initial velocity off 64 ft per sec from a height of 336 feet then its height t sec after it is projected is defined by the equation h= -16t^2 + 64 t + 336. how many sec after it is projected will it hit the ground?<BR>\n" );
document.write( "..<BR>\n" );
document.write( "When object hits the ground its height will be=0<BR>\n" );
document.write( "0= -16t^2 + 64 t + 336<BR>\n" );
document.write( "-16t^2 + 64 t + 336=0<BR>\n" );
document.write( "divide by -16<BR>\n" );
document.write( "t^2-4t-21=0<BR>\n" );
document.write( "(t-7)(t+3)=0<BR>\n" );
document.write( "t-7=0<BR>\n" );
document.write( "t=7 seconds<BR>\n" );
document.write( "t+3=0<BR>\n" );
document.write( "t=-3 (reject, t&#8805;0)<BR>\n" );
document.write( "ans:<BR>\n" );
document.write( "object will hit the ground 7 seconds after it is projected. </SPAN>\n" );
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