SOLUTION: The problem I am stuck on is this: Find k so that (x+3) is a factor of (x^3+kx^2+kx-15)

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Question 163634: The problem I am stuck on is this:
Find k so that (x+3) is a factor of (x^3+kx^2+kx-15)
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find k so that (x+3) is a factor of (x^3+kx^2+kx-15)
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For (x+3) to be a factor, f(-3) must be zero.
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f(-3) = (-3)^3 + k(-3)^2 + k(-3) - 15
Then -27 + 9k -3k - 15 = 0
And 6k = 42
So k = 7
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Cheers,
Stan H.