SOLUTION: X^4-3x^2-54=0

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Question 694426: X^4-3x^2-54=0
Answer by Ave(106) About Me  (Show Source):
You can put this solution on YOUR website!
substitution a=x^2
a^2-3a-54
(a+6)(a-9)
a=-6
a=9
x^2=9
x=±3
x^2=-6
x=sqrt(6)i
so {-3,3}