SOLUTION: Hello, I am trying to find the solution to this problem If cotangent of theta equals -9/2, find sine of theta I have tried to use the equations: cotangent theta = 1/ tangent

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Question 1072895: Hello, I am trying to find the solution to this problem
If cotangent of theta equals -9/2, find sine of theta
I have tried to use the equations: cotangent theta = 1/ tangent
then:
tangent squared theta + 1 = secant squared theta
so I could then use this formula: secant theta = 1/ cosine of theta
so I could finally use the formula: tangent of theta = sine of theta / cosine of theta.
my final answer was -1.1981
thanks,

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
cotangent of theta equals -9/2, find sine of theta
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cot = x/y
The terminal point is either (-9,2) or (9,-2)
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r = sqrt(x^2+y^2) = sqrt(85)
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sine = y/r = 2/sqrt(85) or -2/sqrt(85)
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my final answer was -1.1981
The sine < -1 --> theta is not a real number.