document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=332461>Question 332461</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have asked this ? earlier with no response.<BR>\n" );
document.write( "A ball is thrown from the top of a roof 320 feet above the ground. The formula h = –16t^2 + 32t + 320 describes the height of the ball above the ground, h, in feet, t seconds after the fall begins. Find the maximum height of the ball, as measured from the ground. Hint: The path of the ball is a parabola, so think about the vertex. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #238281 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=238281\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown from the top of a roof 320 feet above the ground. The formula h = –16t^2 + 32t + 320 describes the height of the ball above the ground, h, in feet, t seconds after the fall begins. Find the maximum height of the ball, as measured from the ground. Hint: The path of the ball is a parabola, so think about the vertex.<BR>\n" );
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document.write( "h = –16t^2 + 32t + 320<BR>\n" );
document.write( "The vertex is a point (t,h) where the parabola is at its peak.<BR>\n" );
document.write( "\"axis of symmetry\" provides the \"t\" value of the vertex.<BR>\n" );
document.write( "The value is:<BR>\n" );
document.write( "t = -b/(2a) = -32/(2(-16))<BR>\n" );
document.write( "t = -32/-32<BR>\n" );
document.write( "t = 1 second<BR>\n" );
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document.write( "h value is found by plugging it back into the equation:<BR>\n" );
document.write( "h = –16t^2 + 32t + 320<BR>\n" );
document.write( "h = –16(1)^2 + 32(1) + 320<BR>\n" );
document.write( "h = –16 + 32 + 320<BR>\n" );
document.write( "h = 16 + 320<BR>\n" );
document.write( "h = 336 feet (this is your answer) </SPAN>\n" );
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