document.write( "Question 1058385: from the top of a cliff the angles of depression of two boats in the same vertical plane at the observer's eyes are 30 E and 45. if the distance between the boats is 100 feet, find the height of the cliff \n" ); document.write( "
Algebra.Com's Answer #673438 by Boreal(15235)\"\" \"About 
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Draw this and the angle from the boat to the cliff is 30 degrees.
\n" ); document.write( "The other boat has an angle of 45 degrees.
\n" ); document.write( "The cliff height is x
\n" ); document.write( "the distance to the first boat is y, to the second boat y+100
\n" ); document.write( "tangent 30=x/(y+100)
\n" ); document.write( "tangent 45=x/y
\n" ); document.write( "Therefore, y=x, since tan 45=1
\n" ); document.write( "sqrt(3)/3=x/(x+100) substituting and knowing tan 30 is sqrt (3)/3
\n" ); document.write( "0.5774(x+100)=x
\n" ); document.write( "0.5774x+57.74=x
\n" ); document.write( "57.74=0.4226 x
\n" ); document.write( "dividing out
\n" ); document.write( "136.63 or 136 feet.\r
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