document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1049275>Question 1049275</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rock is thrown upward with a velocity of 21 meters per second from the top of a 48 meter high cliff, and it misses the cliff on the way back down.  When will the rock be 7 meters from the water, below?  Round your answer to two decimal places.<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 #664992 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=664992\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A rock is thrown upward with a velocity of 21 meters per second from the top of a 48 meter high cliff, and it misses the cliff on the way back down.  When will the rock be 7 meters from the water, below?  Round your answer to two decimal places.<BR>\n" );
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document.write( "You didn't supply the acceleration of Earth's gravity.<BR>\n" );
document.write( "sometimes -10 m/sec/sec is used.<BR>\n" );
document.write( "sometimes -9.8 m/sec/sec is used.<BR>\n" );
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document.write( "Using 10 m/sec/sec:<BR>\n" );
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document.write( "h(t) = -5t^2 + 21t + 48<BR>\n" );
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document.write( "-5t^2 + 21t + 48 = 7<BR>\n" );
document.write( "Solve for t.<BR>\n" );
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