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    (Original post by iamspiderman)



    How would I start this question?
    Start the question by using the sine rule to find angle BCA.

    If you're still stuck, post all your working / ideas.
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    (Original post by iamspiderman)



    How would I start this question?
    Use the Sine Law.

    sin(a) divided by side length A (opposite angle a), etc.
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    (Original post by iamspiderman)



    How would I start this question?
    We end up with:

    6sin(45)=5sin(C)
    sin(C) = 4243/5000
    C=58.06 deg.

    Angle B, therefore, has to be 76.94 deg.
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    (Original post by Schmeckel)
    full solution
    Please don't post full solutions - it's against the rules of this forum.

    Your previous post was enough for the OP to get started and your solution was unnecessary.
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    (Original post by iamspiderman)
    Well I basically got the opposite of what you got.
    I did
    Sin45/5 = sinC /6

    How are you meant to know which angle goes with which side ?




    Ok thanks
    Oh, I cross-multiplied to get rid of all those messy fractions.
    6*(sin45/5)=(sinC/6)*5

    That makes them both fractions with 30 as the denominator and then you can cancel them out.

    Angle A is directly opposite side a. Angle B is directly opposite side b. Angle C is directly opposite side c.
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    (Original post by iamspiderman)
    Well I basically got the opposite of what you got.
    I did
    Sin45/5 = sinC /6

    How are you meant to know which angle goes with which side ?
    Ok thanks
    If you rearrange that you get:

    6sin(45) = 5sin(C)

    which is the same as schmeckel's solution.

    From your line, you should multiply both sides by 6 to get

    sin(C) = 6sin(45)/5

    Do you know what to do next?
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    (Original post by Schmeckel)
    Angle B, therefore, has to be 76.94 deg.
    As well as the complete solution issue that has been mentioned

    The OP was not looking for angle B they are asked for angle C
 
 
 
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