document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=53784>Question 53784</A>: <I><SPAN STYLE=\"word-break: break-all;\"> i've tried this questin but i don't get how to do it.\r<BR>\n" );
document.write( "\n" );
document.write( "Michelle threw a ball vertically upwards, with its height h, in metres, after a time of t seconds, being given the formula:<BR>\n" );
document.write( "h=8t-t^2\r<BR>\n" );
document.write( "\n" );
document.write( "Q. find after what time the ball is first at a height of 12m </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #36015 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=36015\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> h=8t-t^2 <BR>\n" );
document.write( "Q. find after what time the ball is first at a height of 12m<BR>\n" );
document.write( "Let the height be 12m and solve for \"t\" as follows:<BR>\n" );
document.write( "12=8t-t^2<BR>\n" );
document.write( "t^2-8t+12=0<BR>\n" );
document.write( "(t-6)(t-2)=0<BR>\n" );
document.write( "t=2 seconds is the 1st time the ball is at 12m<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );