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    I was looking through my revision guide and this question looked easy until i tried it:
    "A ship sails 12km on a bearing of 050°, then 20km on a bearing of 100°. It then sails directly back to its starting position. CALCULATE this distance to 1 d.p."

    Anyone know how to do this without any drawings but only using the sine/cosine rule?
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    (Original post by NothingButWaleed)
    I was looking through my revision guide and this question looked easy until i tried it:
    "A ship sails 12km on a bearing of 050°, then 20km on a bearing of 100°. It then sails directly back to its starting position. CALCULATE this distance to 1 d.p."

    Anyone know how to do this without any drawings but only using the sine/cosine rule?
    It's a cosine rule question
    Sketch the information and use your sketch and knowledge of bearing/parallel line angle facts to work out the angle between the 12 and 20 km lines.


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    (Original post by gdunne42)
    It's a cosine rule question
    Sketch the information and use your sketch and knowledge of bearing/parallel line angle facts to work out the angle between the 12 and 20 km lines.


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    Wait I dont fully follow...
    Could you give me an example please?
    Thanks!
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    (Original post by NothingButWaleed)
    Wait I dont fully follow...
    Could you give me an example please?
    Thanks!
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    (Original post by gdunne42)
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    I figured out how to work out the right question mark but no hope for the left one...
    How do you work out the "?" angle?
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    (Original post by NothingButWaleed)
    I figured out how to work out the right question mark but no hope for the left one...
    How do you work out the "?" angle?
    You need to revise parallel line angle facts.
    Alternate angles are equal


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    (Original post by gdunne42)
    You need to revise parallel line angle facts.
    Alternate angles are equal


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    Yeah I know those rules but if i used them the interior angles is 210 degrees which it cant be as angles add up to 180 in a triangle thats why im confused!
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    (Original post by gdunne42)
    You need to revise parallel line angle facts.
    Alternate angles are equal


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    Oh no never mind I figured out my mistake yeah i got it at the end thanks for our help!!
 
 
 
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