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Math Help - given triangle ABC.....

  1. #1
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    given triangle ABC.....

    The question is:
    Given the triangle ABC with AB=5 and BC= 5sqrt3/3

    The measure of the angle A is 30 degrees. How many choices are there for the measure of angle C?

    I've hit a problem with the final solution.

    sin(c)/5= sin(30degrees)/(5sqrt3/3)
    multiply both sides by 5
    =>sin(c)=(1/2)/(sqrt3/3)
    =(1/2)(3/sqrt3)
    =sqrt3/2

    since Im dealing with sin, I reference the unit circle and see that sin is sqrt3/2 at pi/3 and 2pi/3.

    That means I have 2 choices for angle C?
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  2. #2
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    Quote Originally Posted by ninobrn99 View Post
    The question is:
    Given the triangle ABC with AB=5 and BC= 5sqrt3/3

    The measure of the angle A is 30 degrees. How many choices are there for the measure of angle C?

    I've hit a problem with the final solution.

    sin(c)/5= sin(30degrees)/(5sqrt3/3)
    multiply both sides by 5
    =>sin(c)=(1/2)/(sqrt3/3)
    =(1/2)(3/sqrt3)
    =sqrt3/2

    since Im dealing with sin, I reference the unit circle and see that sin is sqrt3/2 at pi/3 and 2pi/3.

    That means I have 2 choices for angle C?
    As long as the two angles aren't greater than 180, you should be fine since all 3 angles need to equal 180.
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  3. #3
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    Thank you dw!
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