SOLUTION: Find: sin A if cos A = -(3/5) and 90 degrees < A

SOLUTION: Find: sin A if cos A = -(3/5) and 90 degrees < A < 180 degrees

Question 149406: Find:
sin A if cos A = -(3/5) and 90 degrees < A < 180 degrees
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Find:
sin A if cos A = -(3/5) and 90 degrees < A < 180 degrees
If cosA = -3/5, x = -3 , r = 5 in the 2nd quadrant.
Then y = sqrt(r^2-x^2) = sqrt(25-9] = sqrt(16) = 4
Then sinA = y/r = 4/5
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Cheers,
Stan H.
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