SOLUTION: Solve the equation x^4 - 8x^2 - 9 = 0. Find only the real number solutions.

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Question 338597: Solve the equation x^4 - 8x^2 - 9 = 0. Find only the real number solutions.
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
x^4 - 8x^2 - 9 = 0
can be factored as:
(x^2-9)(x^2+1) = 0
(x-3)(x+3)(x^2+1) = 0
x = {-3, 3}