document.write( "Question 730613: From the top of a 210-ft lighthouse, the angle of depression to a ship in the ocean is 15 degrees. How far is the ship from the base of the lighthouse?
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Algebra.Com's Answer #853033 by ikleyn(53427) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "From the top of a 210-ft lighthouse, the angle of depression to a ship in the
\n" ); document.write( "ocean is 15 degrees. How far is the ship from the base of the lighthouse?
\n" ); document.write( "A. 874ft
\n" ); document.write( "B. 478ft
\n" ); document.write( "C. 784ft
\n" ); document.write( "D. 748ft
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document.write( "An equation to use is\r\n" );
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document.write( "    h = d*tan(a),\r\n" );
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document.write( "where h is the height of the lighthouse and d is the distance from the ship to the base of the lighthouse.\r\n" );
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document.write( "We assume that the Earth is flat (and the water surface in the ocean is flat, too) and that\r\n" );
document.write( "the base of the lighthouse is at the level of water surface.\r\n" );
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document.write( "So, our equation is\r\n" );
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document.write( "    210 = d*tan(15°),\r\n" );
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document.write( "    d =  =  = 783.73 feet.\r\n" );
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document.write( "ANSWER.  The closest answer in the list is option (C).\r\n" );
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\n" ); document.write( "\n" ); document.write( "The answer in the post by @lynnlo is incorrect.\r
\n" ); document.write( "\n" ); document.write( "Simply ignore it.\r
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