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Solve the following triangle using either the law of sines or the law of cosines b=6 , c=12, A=48°

User Yesnik
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1 Answer

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Answer:

(a, B, C) ≈ (9.15, 29.2°, 102.8°)

Explanation:

The given angle lies between the given sides, so the law of sines cannot be used. The third side is ...

a² = b² +c² -2bc·cos(A) ≈ 83.6452

a ≈ √83.6452 ≈ 9.146

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Then angle B is found from the law of sines. We want to find the smaller angle, so we can tell if the triangle is acute or obtuse.

sin(B)/b = sin(A)/a

B = arcsin(b/a·sin(A)) ≈ arcsin(0.48753)

B ≈ 29.2°

C = 180° -48° -29.2° = 102.8°

The solution to the triangle is (a, B, C) = (9.1, 29.2°, 102.8°).

Solve the following triangle using either the law of sines or the law of cosines b-example-1
User Muzza
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