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Find BC. A. 22.5 in B. 29 in C. 30 in D. 28 in

Find BC. A. 22.5 in B. 29 in C. 30 in D. 28 in-example-1
User Hjm
by
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1 Answer

5 votes

Answer: B. 29 mi (which you typed 29 in)

Explanation:

Use law of cosine to solve: a²=b²+c²-2bc·cosA (the corresponding angle)

a²=19²+12²-2×19×12×cos (138)

a²=361+144-456cos(138)

a²=505-456cos(138)

a²=843.874 (rounded)

a=29 mi

User Atanisha
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