HOW can I find the displacement of a sailboat tacking against the wind?

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To find the displacement of a sailboat tacking against the wind, the vectors of its movements must be added together. The sailboat travels 2.8 km at 27° east of north, 4.7 km at 28° west of north, and 3.9 km at 28° east of north. The calculations for the x and y components of the displacement are crucial, with the current answer indicating a potential math error. The corrected displacement magnitude is approximately 9.943 km, though some calculations yield slightly different results. Ensuring accurate arithmetic is essential for determining the correct displacement.
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HOW can I not get this??

5. [1pt] A sailboat tacking against the wind moves as follows: 2.8 km at 27° east of north, 4.7 km at 28° west of north, and 3.9 km at 28° east of north. The entire trip takes 4 h 25 min. What is the magnitude of the displacement of the sailboat at the end of the trip ?

Translated: Add the vectors in the question.

Current answer:
/\x = 2.8*sin(27) + 4.7*sin(-28) + 3.9*sin(28) = .805 km
/\y = 2.8*cos(27) + 4.7*cos(-28) + 3.9*cos(28) = 9.910 km
/\d = sqr(/\x2 + /\y2) = 9.943 km = 9943m

What's wrong?
 
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Looks like you've got a math error. try emtering it into your calculator again. I get a little over 10 when I do it BTW.
 
Check your arithmetic. I get (slightly) different answers for \Delta x and \Delta y.
 
Thanks, got it. At least it wasn't a logic error.
 
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