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    Hi,
    I'm really bad at bearings and mechanics in general and I can't get the right answer to this question. Please help!

    A man walks 5 km from O on a bearing of 290° to a point A. He then walks a further distance of 2 km on a bearing of 045° to a point B. Find the distance OB and the bearing of O from B.

    Please look at my diagram that I attached and tell me if it is right?
    I got the distance OB right (4.53km) but I can't get the bearing right. Apparently it is 314° but if you look on my diagram it is impossible to get this!

    What am I doing wrong?!
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    (Original post by xsweetcherrypiex)
    Hi,
    I'm really bad at bearings and mechanics in general and I can't get the right answer to this question. Please help!

    A man walks 5 km from O on a bearing of 290° to a point A. He then walks a further distance of 2 km on a bearing of 045° to a point B. Find the distance OB and the bearing of O from B.

    Please look at my diagram that I attached and tell me if it is right?
    I got the distance OB right (4.53km) but I can't get the bearing right. Apparently it is 314° but if you look on my diagram it is impossible to get this!

    What am I doing wrong?!
    You're not doing anything wrong. As you noted, the bearing can't be 314.

    Your diagram looks fine, as does your reasoning.

    Assuming you have the question down correctly, then there's an error somewhere in the book.
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    You have drawn the bearing from B to O, not the bearing from O to B. Think about the angle between the North line above O and B is.
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    (Original post by Ben121)
    You have drawn the bearing from B to O, not the bearing from O to B. Think about the angle between the North line above O and B is.
    But I thought when it says the bearing of O from B, they mean the clockwise angle from the North line above B to O, since it is from B to O?
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    (Original post by ghostwalker)
    You're not doing anything wrong. As you noted, the bearing can't be 314.

    Your diagram looks fine, as does your reasoning.

    Assuming you have the question down correctly, then there's an error somewhere in the book.
    Thank you! Mechanics always gets me really worried!
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    how did you get the distance of OB
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    (Original post by BrightStar57)
    how did you get the distance of OB
    Work out the angles, and then use the cosine rule.
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    thankyou xx, but please could you show me how to work out the angles am reallyyy baad at bearings and seriously need some mega help ....
 
 
 
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