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Math Help - Trig Question

  1. #1
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    Trig Question

    Hi
    I need some help on the following question:
    In the triangle ABC to calculate the lengths of sides AB and BC.



    P.S
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  2. #2
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    Dear Paymemoney,

    Consider Sin 27 and Tan 27 and relate them to the length that is given. If you need more help please don't hesitate to reply me.
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  3. #3
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    ok this is what i have done, but it is incorrect.

    \frac{15}{sin90}=\frac{b}{sin27}

    15sin27=bsin90

    \frac{15sin27}{sin90}=b

    b=16.04
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  4. #4
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    Quote Originally Posted by Paymemoney View Post
    Hi
    I need some help on the following question:
    In the triangle ABC to calculate the lengths of sides AB and BC.



    P.S
    You should know that

    \sin{\theta} = \frac{\textrm{Opposite}}{\textrm{Hypotenuse}}

    and

    \tan{\theta} = \frac{\textrm{Opposite}}{\textrm{Adjacent}}.


    Label the sides of your triangle, substitute the values into your equations as appropriate, and solve for the unknown sides.
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  5. #5
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    Dear Paymemoney,

    The way you did is incorrect. I assume that you tried to use the Sine rule. But you have applied it incorrectly. In the first line you have written it should be 15/Sin27=BC/Sin90. But as "Prove It" had shown it could be done easily if you consider the Trignometric ratios of right traingles.
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  6. #6
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    ok thanks i got the solutions.
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