SOLUTION: how do you write a quadratic equation with a root of 2-5i ?

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Question 390066: how do you write a quadratic equation with a root of 2-5i ?
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
%28x-%282-5i%29%29%28x+-+%282%2B5i%29%29+=+%28%28x-2%29%2B5i%29%28%28x+-+2%29-5i%29%29
= %28x-2%29%5E2+-+25i%5E2+=+x%5E2+-+4x+%2B+4+%2B+25+=+x%5E2+-+4x+%2B+29+=+0.
Thus any quadratic equation a%28x%5E2+-+4x+%2B+29%29+=+0, where a is not equal to 0, will have 2 - 51 as root.
(Note that if A + Bi is a root of the quadratic equation, then so is its conjugate A - Bi.)