document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206150>Question 1206150</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown vertically upward with an initial velocity of 48  feet per second. The distance s​ (in feet) of the ball from the ground after t seconds is  s=48t−16t2<BR>\n" );
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document.write( "(a) At what time t will the ball strike the​ ground?<BR>\n" );
document.write( "​(b) For what time t is the ball more than 20 feet above the​ ground? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #843404 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=843404\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A ball is thrown vertically upward with an initial velocity of 48 feet per second. The distance s​ (in feet) of the ball from the ground after t seconds is s=48t−16t2<BR>\n" );
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document.write( "(a) At what time t will the ball strike the​ ground?\r<BR>\n" );
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document.write( "at t=0 the ball is on ground\r<BR>\n" );
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document.write( "S(t)=0 = 48t-16t^2\r<BR>\n" );
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document.write( "Solve for t\r<BR>\n" );
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document.write( "16t^2=48t\r<BR>\n" );
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document.write( "t=3s\r<BR>\n" );
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document.write( "​(b) For what time t is the ball more than 20 feet above the​ ground?\r<BR>\n" );
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document.write( "Between two times it is above 20 ft\r<BR>\n" );
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document.write( "48t-16t^2 >20\r<BR>\n" );
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document.write( "Solve the inequality  to get the time (s)\r<BR>\n" );
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document.write( " </SPAN>\n" );
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