document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1013229>Question 1013229</A>: <I><SPAN STYLE=\"word-break: break-all;\"> . An airplane is flying 10,500 ft. above the ground. The angle of depression from the plane to the base of a tree<BR>\n" );
document.write( "is 13o<BR>\n" );
document.write( "50’. How far horizontally must the plane fly to be directly over the tree?\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "I've been trying to answer this question but I really don't understand it. I'm also not ale to attend the discussion. Can you help me? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #629480 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=629480\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i'm not sure where the 50 feet comes from.<BR>\n" );
document.write( "let me see what i can do without that.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the plane is flying at 10,500 feet.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the angle of depression from the plane to the base of the tree is 13 degrees, if i understand that correctly.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the angle of depression is the angle that is formed by drawing a line that is 13 degrees from the horizontal line formed by the plane.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "see the following reference for a discussion of angle of elevation and angle of depression.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<a  rel=nofollow HREF= \"http://www.purplemath.com/modules/incldecl.htm\" target = \"_blank\">http://www.purplemath.com/modules/incldecl.htm</a>\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "you have two horizontal lines at AD and CB.<BR>\n" );
document.write( "you have two vertical lines at AC and DB.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the length of line AC is equal to the length of DB.<BR>\n" );
document.write( "the length of AD is equal to the length of CB.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the angles at A, B, C, D, are all 90 degrees.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "ADBC is therefore a rectangle.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the length of AD and CB is represented by x in the diagram.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "since line AD and CB are parallel, and since line AB is a transversal of those two parallel lines, then angle DAB is congruent to angle ABC, so they're both equal to 13 degrees.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "tan(angle ABC) = tan(13) = 10500 / x.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "solve for x to get x = 10500 / tan(13) = 45480.49668.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x is the horizontal distance from the plane to the point D directly above the foot of the tree at point B.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "that's your solution.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x = 45480.49668 feet.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "round as you see fit.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "here's the diagram of the triangles and rectangle formed.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2016/011102.jpg\" alt=\"$$$\" </>\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );