document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=714990>Question 714990</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 17 From the top of a vertical cliff 68 m high, an observer<BR>\n" );
document.write( "notices a yacht at sea. The angle of depression to the<BR>\n" );
document.write( "yacht is 47è. The yacht sails directly away from the cliff,<BR>\n" );
document.write( "and after 10 minutes the angle of depression is 15è. How<BR>\n" );
document.write( "fast does the yacht sail? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #439253 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=439253\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28400%2C120%2C-13%2C266%2C-8%2C76%2C%0D%0Aline%28-13%2C68%2C0%2C68%29%2Cline%280%2C68%2C0%2C-8%29%2C%0D%0Ablue%28line%280%2C0%2C260%2C0%29%29%2C%0D%0Agreen%28line%280%2C68%2C63.4%2C0%29%29%2Cred%28line%280%2C68%2C253.8%2C0%29%29%2C%0D%0Alocate%2865%2C0%2CX%29%2Clocate%28250%2C0%2CY%29%2C%0D%0Alocate%282%2C0%2CB%29%2Clocate%282%2C76%2CT%29%2C%0D%0Arectangle%280%2C0%2C5%2C5%29%2Clocate%282%2C35%2C68%29%2C%0D%0Aline%280%2C68%2C5%2C68%29%2Cline%2810%2C68%2C15%2C68%29%2Cline%2820%2C68%2C25%2C68%29%2C%0D%0Aline%2830%2C68%2C35%2C68%29%2Cline%2840%2C68%2C45%2C68%29%2Cline%2850%2C68%2C55%2C68%29%2C%0D%0Aline%2860%2C68%2C65%2C68%29%2Cline%2870%2C68%2C75%2C68%29%2Cline%2880%2C68%2C85%2C68%29%2C%0D%0Aline%2890%2C68%2C95%2C68%29%2Cline%28100%2C68%2C105%2C68%29%2Cline%28110%2C68%2C115%2C68%29%2C%0D%0Aline%28120%2C68%2C125%2C68%29%2Cline%28130%2C68%2C135%2C68%29%2Cline%28140%2C68%2C145%2C68%29%2C%0D%0Aline%28150%2C68%2C155%2C68%29%2C%0D%0Alocate%28157%2C68%2CH%29%0D%0A%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "T = top of the cliff (we assume eye of observer is there, 68 meters above water surface)<BR>\n" );
document.write( "B = bottom of the cliff (at water level)<BR>\n" );
document.write( "X = initial position of the yacht<BR>\n" );
document.write( "Y = position of the yacht 10 minutes later<BR>\n" );
document.write( "TH = a horizontal line, parallel to BY.<BR>\n" );
document.write( "angle HTX = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=47%5Eo ALIGN=MIDDLE  ALT=\"47%5Eo\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> Angle BTX = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=90%5Eo-47%5Eo=43%5Eo ALIGN=MIDDLE  ALT=\"90%5Eo-47%5Eo=43%5Eo\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "angle HTY = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15%5Eo ALIGN=MIDDLE  ALT=\"15%5Eo\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> Angle BTY = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=90%5Eo-15%5Eo=75%5Eo ALIGN=MIDDLE  ALT=\"90%5Eo-15%5Eo=75%5Eo\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=BX=68m%2Atan%2843%5Eo%29=68m%2A0.93255=63.4m ALIGN=MIDDLE  ALT=\"BX=68m%2Atan%2843%5Eo%29=68m%2A0.93255=63.4m\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=BY=68m%2Atan%2875%5Eo%29=68m%2A3.732=253.8m ALIGN=MIDDLE  ALT=\"BY=68m%2Atan%2875%5Eo%29=68m%2A3.732=253.8m\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The yacht  covered<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=253.8m-63.4m=190.4m ALIGN=MIDDLE  ALT=\"253.8m-63.4m=190.4m\"   DISABLED_style= \"max-width:90%; height:auto;\" > in 10 minutes.<BR>\n" );
document.write( "We could say that its speed in meters per minute is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=190.4%2F10=19 ALIGN=MIDDLE  ALT=\"190.4%2F10=19\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );