document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1166061>Question 1166061</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown upward with an initial velocity of 30 feet per second from a point that is 24 feet above the ground. The height (h) in feet of the ball at time t (in second) is given by the equation: h(t)= -16t^2+30t+24<BR>\n" );
document.write( "a) at what time did the ball reach its maximum height?<BR>\n" );
document.write( "b) what was the maximum height? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #790541 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=790541\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The maximum height is reached when the derivative dh/dt = 0:<BR>\n" );
document.write( "dh/dt = -32t + 30 = 0<BR>\n" );
document.write( "This gives t = 30/32 = 0.9375 s<BR>\n" );
document.write( "h(0.9375) = -16*(0.9375)^2 + 30*0.9375 + 24 = 38.063 ft </SPAN>\n" );
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