document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=301613>Question 301613</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height of a ball in feet is modeled as f(x)=-16x^2+96x, where x is the time in seconds after it is hit. How long is the ball in the air? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #216254 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=216254\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The height of a ball in feet is modeled as f(x)=-16x^2+96x, where x is the time in seconds after it is hit. How long is the ball in the air?<BR>\n" );
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document.write( "The time it is in the air is equivalent to the time it hits the ground -- so, set f(x) to 0 and solve for t:<BR>\n" );
document.write( "f(x)=-16x^2+96x<BR>\n" );
document.write( "0=-16x^2+96x<BR>\n" );
document.write( "0=16x^2-96x<BR>\n" );
document.write( "0=x^2-6x<BR>\n" );
document.write( "0=x(x-6)<BR>\n" );
document.write( "x = {0,6}<BR>\n" );
document.write( "Solution: 6 seconds<BR>\n" );
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