document.write( "Question 233387: Points A and B are separated by a lake. To find the distance between them, a surveyor locates a point C on land such that angleCAB = 48.6°. He also measures CA as 316 ft and CB as 527 ft. Find the distance between A and B. Round your answer to the nearest foot. (Note: angleABC is an acute angle.) \n" ); document.write( "
Algebra.Com's Answer #172300 by Theo(13342)\"\" \"About 
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Drop a line perpendicular to line AC and intersecting line AC at point D.\r
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\n" ); document.write( "\n" ); document.write( "That forms 2 right triangles.\r
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\n" ); document.write( "\n" ); document.write( "First is triangle ACD and second is triangle BCD.\r
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\n" ); document.write( "\n" ); document.write( "You have:\r
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\n" ); document.write( "\n" ); document.write( "AC = 316 feet (given)
\n" ); document.write( "BC = 527 feet (given)
\n" ); document.write( "angle CAB = 48.6 degrees (given)
\n" ); document.write( "angle CAD = 58.6 degrees also because it's the same angle.\r
\n" ); document.write( "\n" ); document.write( "sin(CAD) = CD / AC
\n" ); document.write( "This becomes:
\n" ); document.write( "sin(48.6) = CD / 316
\n" ); document.write( "multiply both sides of this equation to get:
\n" ); document.write( "316 * sin(48.6) = CD
\n" ); document.write( "This makes CD = 237.035098\r
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\n" ); document.write( "\n" ); document.write( "We use the value of CD to get angle CBD\r
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\n" ); document.write( "\n" ); document.write( "sin(CBD) = CD / 527
\n" ); document.write( "This becomes:
\n" ); document.write( "sin(CBD) = 237.035098/527 = .44978197
\n" ); document.write( "This makes angle CBD = 26.72969621 degrees.\r
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\n" ); document.write( "\n" ); document.write( "We can now find AD and BD.\r
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\n" ); document.write( "\n" ); document.write( "cos(CAD) = AD / AC
\n" ); document.write( "This becomes:
\n" ); document.write( "cos(48.6) = AD / 316
\n" ); document.write( "multiply both sides of this equation by 316 to get:
\n" ); document.write( "316 * cos(48.6) = AD
\n" ); document.write( "This makes AD = 208.9745494 feet.\r
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\n" ); document.write( "\n" ); document.write( "cos(CBD) = BD / BC
\n" ); document.write( "multiply both sides of this equation by BC to get:
\n" ); document.write( "BC * cos(CBD) = BD
\n" ); document.write( "This becomes:
\n" ); document.write( "527 * cos(26.72969621) = BD
\n" ); document.write( "This makes BD = 470.6859304 feet\r
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\n" ); document.write( "\n" ); document.write( "Total length of AB = AD + BD = 208.9745494 + 470.6859304 = 679.6584798 feet.\r
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