SOLUTION: x^4+10x^2+9=0 solve as quadratic function? my assumption is x^2=-1 and x^2=-9 which there is no real solution but i dont think i am right

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Question 240910: x^4+10x^2+9=0
solve as quadratic function?
my assumption is
x^2=-1 and x^2=-9
which there is no real solution but i dont think i am right
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve:
x%5E4%2B10x%5E2%2B9+=+0 Rewrite this as:
%28x%5E2%29%5E2%2B10%28x%5E2%29%2B9+=+0 Factor.
%28x%5E2%2B1%29%28x%5E2%2B9%29+=+0 Apply the zero product rule.
x%5E2%2B1+=+0 or x%5E2%2B9+=+0 so...
If x%5E2%2B1+=+0 then x%5E2+=+-1 so x+=+sqrt%28-1%29 or x+=+-sqrt%28-1%29
If x%5E2%2B9+=+0 then x%5E2+=+-9 so x+=+sqrt%28-9%29 or x+=+-sqrt%28-9%29
These answers can be written as: (Note: i+=+sqrt%28-1%29)
x+=+i
x+=+-i
x+=+3i
x+=+-3i
You are correct in stating that there are no REAL solutions, the solutions are complex.