document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=123779>Question 123779</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534404693/algebrahomeworkh>algebra and trigonometry with analiytic geometry</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> When a rock is dropped from a cliff into an ocean, it travels approximately 16t^2 feet in t seconds. If the splash is heard 5.5 seconds later and the speed of sound is 1100 ft/sec, approximate the height of the cliff.\r<BR>\n" );
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document.write( "Please round the answer to the whole number.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #90803 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=90803\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When a rock is dropped from a cliff into an ocean, it travels approximately 16t^2 feet in t seconds. If the splash is heard 5.5 seconds later and the speed of sound is 1100 ft/sec, approximate the height of the cliff.<BR>\n" );
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document.write( "Let the time to hit the water be \"x\" seconds; distance to the water =16x^2 ft<BR>\n" );
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document.write( "Time sound takes to the listener is \"5.5-x\" seconds;<BR>\n" );
document.write( "distance from spash to listener is 1100(5.5-x) = (6050-1100x) ft.<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "distance down  distance up<BR>\n" );
document.write( "16x^2 = -1100x+6050<BR>\n" );
document.write( "16x^2+1100x-6050 = 0<BR>\n" );
document.write( "I graphed it and found x = 5.1189<BR>\n" );
document.write( "Note: You could use the quadratic formula and get the same answer.<BR>\n" );
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document.write( "Height of the cliff = 16(5.1199^2) = 419.25 ft.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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