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Find the area of triangle ABC if B=30 degrees, C=120 degrees, and a=4.

absinC
4*4*sin120
16*sin120
13.86

I got it wrong

The area is not a b sin C. It is
(1/2)[a^2 sin A + b^2 sin B]
This equals a^2 sin A in this case, for which a = b and A = B

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