In triangle ABC, A = 40 degrees, B = 70 degrees and a = 8. What is b, to one decimal?
Answer and explanation
Correct answer: A. 11.7, from b = 8 sin 70 / sin 40
- Step 1: The sine law gives b/sin B = a/sin A. Step 2. b = 8(0.9397)/0.6428 = 11.7. Answer: 11.7. Why not the others: the other values invert the ratio, omit the division or use cosine.
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