document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=211669>Question 211669</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A soccer ball is kicked straight up with an initial velocity of 32 ft. per second. Its height above the earth is given by s (t) = -16t^2 + 32t, where,‘s’ is the height in ft. at any time, ‘t’ seconds. \r<BR>\n" );
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document.write( "What is the maximum height reached by the ball?<BR>\n" );
document.write( "How long after it was thrown up the ball reaches its maximum height?		<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #159971 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=159971\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> s(t) = -16t^2 + 32t<BR>\n" );
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document.write( "One way to find the time to max height is to solve for the 2 times when the ball is at ground level, s = 0, and divide by 2.  It takes the same amount of time to ascend as to descend.<BR>\n" );
document.write( "-16t^2 + 32t = 0<BR>\n" );
document.write( "t(-16t + 32) = 0<BR>\n" );
document.write( "t = 0 (at the start)<BR>\n" );
document.write( "t = 2 (at impact)<BR>\n" );
document.write( "The time at max height is 1 second.<BR>\n" );
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document.write( "For max height:<BR>\n" );
document.write( "s(1) = -16*1 + 32*1<BR>\n" );
document.write( "s max = 16 feet<BR>\n" );
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