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marium mustafa
Sep 30, 2009, 09:18 AM
The point B is 280m due north of point A. A man walks from A in the direction 050(degrees). Calculate how far he has to walk before he is as close as possible to B

marium mustafa
Sep 30, 2009, 09:41 AM
(b) as close as possible to B means that the line BD is perpendicular to the 050 bearing line and so AB is a hypotenuse

So use the basic cosine ratio:

cos 50 = BD/280

BD = 280 cos 50

BD = 179.98

So after walking for 180 m he is as close to B as he is going to get on the 050 bearing