document.write( "Question 1171560: To determine the distance across a lake, a surveyor selected two points P and Q, one on each shore and directly
\n" ); document.write( "opposite each other. On the shore containing P, another point R was chosen, 50 ft from P, so that the line segment PR
\n" ); document.write( "was perpendicular to the line segment PQ. The angle having the sides PR and PQ was measured to be 78.24°. What
\n" ); document.write( "is the distance across the lake? Round off your answer to two decimal places.
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Algebra.Com's Answer #796504 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "Diagram
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\n" ); document.write( "The surveyor is on the side labeled \"shore 1\". Point Q could be any landmark on the opposite shore such as a rock or tree.\r
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\n" ); document.write( "\n" ); document.write( "I think your teacher made a typo and should have said \"The angle having the sides PR and QR was measured to be 78.24°\". The angle having sides PR and PQ is the 90 degree angle. \r
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\n" ); document.write( "\n" ); document.write( "Based on the diagram above, we know that,
\n" ); document.write( "tan(angle) = opposite/adjacent
\n" ); document.write( "tan(angle R) = PQ/PR
\n" ); document.write( "tan(78.24) = x/50
\n" ); document.write( "50*tan(78.24) = x
\n" ); document.write( "x = 50*tan(78.24)
\n" ); document.write( "x = 240.174013162624
\n" ); document.write( "x = 240.17
\n" ); document.write( "Make sure your calculator is in degree mode.\r
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\n" ); document.write( "\n" ); document.write( "Answer: The distance across the lake is approximately 240.17 feet
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