SOLUTION: If the sine of an angle is 3/5 and the angle is not in Quadrant 1, what is the value of the cosine and angle?

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Question 286992: If the sine of an angle is 3/5 and the angle is not in Quadrant 1, what is the value of the cosine and angle?
Answer by dabanfield(803) About Me  (Show Source):
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If the sine of an angle is 3/5 and the angle is not in Quadrant 1, what is the value of the cosine and angle?
The hypotenuse of the triangle formed is 5 and the opposite leg is 3. If the adjacent leg is x we know by the Pythagorean Theorem:
x^2 + 3^2 = 5^5
x^2 = 25-9
x^2 = 16
x = 4
The cosine of the angle then is adjacent/hypotenuse = 4/5.
The angle whose sine is .6 is ? (use the trig tables)