document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=345413>Question 345413</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if a model rocket is propelled upward from ground level at an initial velocity of 112 feet per second, after t seconds, its height h is given by the formula h= -16t^2 + 112t. After how many seconds will its height be 192 feet? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #247052 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=247052\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Given:<BR>\n" );
document.write( "h= -16t^2 + 112t<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Set h = 192 and solve for t:<BR>\n" );
document.write( "192 = -16t^2 + 112t<BR>\n" );
document.write( "0 = -16t^2 + 112t - 192<BR>\n" );
document.write( "dividing both sides by -16:<BR>\n" );
document.write( "0 = t^2 - 7t + 12<BR>\n" );
document.write( "factoring:<BR>\n" );
document.write( "0 = (t-3)(t-4)<BR>\n" );
document.write( "t = {3, 4}<BR>\n" );
document.write( "It will be at 192 feet at 3 and 4 seconds<BR>\n" );
document.write( " </SPAN>\n" );
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