SOLUTION: I can't remember how to "go backwards" in this equation with imaginary numbers! Can you please help explain this problem to me? Write a third degree polynomial equation with ra

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Question 292683: I can't remember how to "go backwards" in this equation with imaginary numbers!
Can you please help explain this problem to me?
Write a third degree polynomial equation with rational coefficients that has roots -5 and 6+i
Thank you!!
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
complex roots occur in conjugate pairs, so 6-i is the third root (third degree)

if r is a root, then x-r is a factor

(x + 5)(x - 6 - i)(x - 6 + i) = 0

multiply the factors out to get the polynomial