Question 438018
In non-right triangle ABC, let A=120 degrees, a = 7cm, and b=3cm. 
Find side c and angles B and C. 
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Use the Law of Sines:
sin(B)/b = sin(A)/a
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sin(B) = (b/a)sin(A)
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sin(B) = (3/7)sin(120) = 0.3712
B = sin^-1(0.3712) = 21.79 degrees
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So C = 180-[21.79+120] = 38.21 degrees
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c/sin(C) = a/sin(A)
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c = sin(C)[a/sin(A)
c = sin(38.21)[7/sin(120)]
c = 5
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Cheers,
Stan H.
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