Math: law of sines, hw help?

Is my answer correct or incorrect?

Update:

Keep in mind I may or may not use the correct answer, Don’t be afraid to disagree! Also if the answer is wrong show me how to get to the right answer!

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  • 4 months ago
    Favorite Answer

    ..a.............b

    -------- = ----------

    ..sin(A)....sin(B)

    ..20.........b

    ------- = --------

    ..2/3........4/5

    16 = 2/3b

    b = 24 Answer//

    I am sad that your answer is incorrect.

    The correct answer is B. 24

  • 4 months ago

    Whatever the triangle, you can apply the Law of sines.

    https://en.wikipedia.org/wiki/Law_of_sines

    a/sin(A) = b/sin(B) = c/sin(C) ← adapt it to your case in the triangle ABC

    20/(2/3) = b/(4/5) = c/sin(C)

    You start the seond equation:

    20/(2/3) = b/(4/5)

    b = [20/(2/3)] * (4/5)

    b = 20 * (3/2) * (4/5)

    b = (20 * 3 * 4)/(2 * 5)

    b = 24

  • 4 months ago

     In ΔABC, sin A = 2/3, sin B = 4/5, and side a = 20. 

     Find side b.

     a / sin A = b / sin B

     20 / (2/3) = b / (4/5)

     30 = 5b / 4

     b = 24

     Answer choice:

     B. 24

  • alex
    Lv 7
    4 months ago

    a/sinA = b/sinB

    ---> b = (sinB / sinA)*a = ...

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