SOLUTION: If 1+2i is a root of X^2-kx+5=0, find the value of k the x^2 means that the x is squared.

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Question 377277: If 1+2i is a root of X^2-kx+5=0, find the value of k
the x^2 means that the x is squared.
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
If 1 + 2i is a root, then 1 - 2i is also a root. Then 1 + 2i + 1 - 2i = -(-k) = k. Thus k = 2.