document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=439858>Question 439858</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height of a projectile fired vertically into the air (neglecting air resistance) at an initial velocity of 160 feet per second is a function of time, x, and is given by the equation f(x) = 160x – 16x2       Find the highest point reached by the projective.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #303978 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=303978\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f(x) = -16x^2 + 160x<BR>\n" );
document.write( "The vertex is on the line of symmetry.<BR>\n" );
document.write( "The line of symmetry is x = -b/2a = -160/-32 = 5<BR>\n" );
document.write( "f(5) = -400 + 800 = 400 feet<BR>\n" );
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