SOLUTION: what is the solution to x^4+5x^2-36=0

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Question 981674: what is the solution to
x^4+5x^2-36=0
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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Let y=x^2
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x^4+5x^2-36=0 Substitute for x^2.
y^2+5y-36=0
(y+9)(y-4)=0
(y+9=0) OR (y-4=0)
(y=-9) OR (y=4) Substitute for y
(x^2=-9) OR (x^2=4)
(x=+ or - 3i) OR (x= + or - 2)