Solve for , to 1 decimal place.
Answer and explanation
Correct answer: B. and
- Step 1: Rearrange: .
- Step 2: Calculator: (second quadrant).
- Step 3: Cosine is also negative in the third quadrant: .
Answer
and .
Why not the others: and : these solve . and : 70.5 has a positive cosine. and : the second solution is .
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