SOLUTION: how would you write a quadratic equation if the answer is x = -4i x = 4i

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Question 326355: how would you write a quadratic equation if the answer is

x = -4i

x = 4i

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
If x=4i and x=-4i, then x-4i=0 and x%2B4i=0.
f%28x%29=%28x-4i%29%28x%2B4i%29
Use the FOIL method,
f%28x%29=x%5E2%2B4ix-4ix-16i%5E2
highlight%28f%28x%29=x%5E2%2B16%29