document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1073930>Question 1073930</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A model rocket is launched with an initial velocity of 180 ft/s. The height, h, in feet, of the rocket t seconds after the launch is given by <BR>\n" );
document.write( "h = &#8722;16t2 + 180t.<BR>\n" );
document.write( "How many seconds after launch will the rocket be 280 ft above the ground? Round to the nearest hundredth of a second.<BR>\n" );
document.write( ".......... (smaller value)<BR>\n" );
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document.write( "............(larger value) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #688725 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=688725\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> By your equation;<BR>\n" );
document.write( "-16tē+180t=280<BR>\n" );
document.write( "16tē-180t+280=0<BR>\n" );
document.write( "4tē-45t+70=0<BR>\n" );
document.write( "Using the quadratic formula, we get two roots of  9.38540223912 and 1.86459776088, or 9.4 and 1.9 seconds after launch. &#9786;&#9786;&#9786;&#9786; </SPAN>\n" );
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