SOLUTION: x^4=7(x^2)+18 Solve for x.

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Question 1025983: x^4=7(x^2)+18
Solve for x.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E4=7%28x%5E2%29%2B18
Solve for x.
Arrange as a quadratic equation
x%5E4+-+7x%5E2+-+18+=+0+
Factor
%28x%5E2-9%29%28x%5E2%2B2%29+=+0
The positive solution is what we want here
x%5E2+=+9
Two solutions
x+=+sqrt%289%29
x = 3
and
x+=+-sqrt%289%29
x = -3
:
looks like this
+graph%28+300%2C+200%2C+-6%2C+6%2C+-50%2C+50%2C+x%5E4-7x%5E2-18%29+