document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=457019>Question 457019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> h= 16t+28f+6,where height,h,is in feet and the time,t,is in seconds.How long does it take for this ball to reach a height of 12 feet? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #313594 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=313594\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I think your formula should be:<BR>\n" );
document.write( "h= -16t^2+28t+6<BR>\n" );
document.write( "Now, you set h to 12 and solve for t:<BR>\n" );
document.write( "12= -16t^2+28t+6<BR>\n" );
document.write( "0 = -16t^2+28t-6<BR>\n" );
document.write( "0 = -8t^2+14t-3<BR>\n" );
document.write( "0 = 8t^2-14t+3<BR>\n" );
document.write( "factoring we have:<BR>\n" );
document.write( "0 = (4t-1)(2t-3)<BR>\n" );
document.write( "t = {1/4, 3/2}<BR>\n" );
document.write( "it reaches a height of 12 feet at:<BR>\n" );
document.write( "1/4 second (on the way up)<BR>\n" );
document.write( "and again at<BR>\n" );
document.write( "3/2 second (on the way down)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );