document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1152649>Question 1152649</A>: <I><SPAN STYLE=\"word-break: break-all;\"> .American astronauts working on a space station on the moon toss a ball into the air. The height of the ball is represented by the equation f(t)=-2.7t^2+13.5t+14 where t represents time in seconds since the ball was thrown and f(t) represents the height of the ball in feet.\r<BR>\n" );
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document.write( "a. When will the ball hit the ground?   seconds (round to the nearest hundredth)\r<BR>\n" );
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document.write( "b. What is the greatest height the ball will reach?    feet (round to the nearest hundredth) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #774699 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=774699\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f(t)=-2.7t^2+13.5t+14<BR>\n" );
document.write( "the vertex or maximum height occurs when t=-b/2a, or -13.5/-5.4 or at 2.5 seconds<BR>\n" );
document.write( "f(2.5)=-2.7(6.25)+13.5(2.5+14=30.875 or 30.88 feet maximum height\r<BR>\n" );
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document.write( "hits the ground when t=0, and want the only positive root when f(t)=0<BR>\n" );
document.write( "can rewrite as 0=2.7t^2-13.5t-14<BR>\n" );
document.write( "quadratic formula<BR>\n" );
document.write( "t=(1/5.4)(13.5+/- sqrt(13.5^2+(151.2))and that sqrt=18.26<BR>\n" );
document.write( "only positive root wanted<BR>\n" );
document.write( "t=(1/5.4)(31.76)<BR>\n" );
document.write( "=5.88 sec\r<BR>\n" );
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