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    Okay so if there is a * next to a number it means degree's.

    Joanne walks 4.2 miles on a bearing 138*. She then walks 7.8 miles on a bearing of 251*.

    a) Calculate how far Joanne is from the point where she started.

    b) Find, as a bearing, the direction in which Joanne would have to walk in order to return to the point where she started.

    Okay so I done a) worked it out to be 7.27 miles. I don't know if that's definitely right but you can check.
    My problem is in part b). I have no clue how to do it. Any help would be appreciated. Thanks
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    Anyone?
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    if u have gotten that side,the rest should be easy.just work out the angle facing a side(i assume u dont have a problem with this).then use sine rule to work out the angle facing the 4.2 side,then work out the bearing.i worked it out to be 040.3*.
    its a bit difficult for me to explain angles you cant see.so i hope by some miracle,this helps.
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    I got 7.27 miles too.

    Use the sine rule to answer part B. You have all 3 sides and 1 angle, and you need to find another angle.

    Draw a diagram.
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    (Original post by AnonyMatt)
    I got 7.27 miles too.

    Use the sine rule to answer part B. You have all 3 sides and 1 angle, and you need to find another angle.

    Draw a diagram.

    Okay, I drew the diagram. Is the bearing I'm trying to find the one I called y (in red) in the attachment. If so, how do I use the sine rule to work that out
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    (Original post by CapsLocke)
    Okay, I drew the diagram. Is the bearing I'm trying to find the one I called y (in red) in the attachment. If so, how do I use the sine rule to work that out
    Call side 7.27 a
    So that sinA = sin67*

    Now notice that y is the same angle as the one... to the left of the north line you've drawn in, opposite the side of length 7.8
    Can you see where I mean?

    This is because the north lines are parallel.

    Anyway, call side 7.8 b
    So that the opposite angle is B
    You can find sinB, and therefore B

    y is then B - (180-138) in degrees. Can you see why?
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    (Original post by AnonyMatt)
    Call side 7.27 a
    So that sinA = sin67*

    Now notice that y is the same angle as the one... to the left of the north line you've drawn in, opposite the side of length 7.8
    Can you see where I mean?

    This is because the north lines are parallel.

    Anyway, call side 7.8 b
    So that the opposite angle is B
    You can find sinB, and therefore B

    y is then B - (180-138) in degrees. Can you see why?

    Ohhh, thanks I get it now.
 
 
 
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