document.write( "Question 1044501: A boat travels 5km NE and then 7km at a bearing of 120degrees. Find its distance and direction from its starting point using vectors. \n" ); document.write( "
Algebra.Com's Answer #659867 by Boreal(15235)\"\" \"About 
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\n" ); document.write( "Start=================Pt 2 (approx)\r
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\n" ); document.write( "\n" ); document.write( "It goes NE (45 deg bearing) for 5 km.
\n" ); document.write( "x value is 5 cos 45 or (5/2) sqrt (2)
\n" ); document.write( "y value is 5 sin 45 or (5/2) sqrt (2)
\n" ); document.write( "the other vector bears 120 degrees
\n" ); document.write( "x value is 7 cos (-30)=(7/2)sqrt (3)
\n" ); document.write( "y-value is 7 sin (-30)=-3.5
\n" ); document.write( "add the two
\n" ); document.write( "x value is (5/2) sqrt (2)+(7/2) sqrt (3) or 9.598
\n" ); document.write( "y value is (5/2) sqrt (2)-3.5 or 0.036
\n" ); document.write( "The distance is the sqrt of each of those squared.
\n" ); document.write( "Numerically it is 9.60 km (rounding only at end)
\n" ); document.write( "Direction is tan (-1) (y/x)=0.036/9.598=0.214 deg above the x-axis or 90.2 deg true
\n" ); document.write( "9.6 km at 90 degrees.
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