SOLUTION: .4 x = 81 its x to the 4th power = 81 I don't know if I'm doing it right (x^+9)(x^-9)=0 (x+3)(x-3)(x+3)(x-3)=0 x-3=0 x=3 x+3=0 x=-3 (3,-3)

Question 144534: .4
x = 81
its x to the 4th power = 81
I don't know if I'm doing it right
(x^+9)(x^-9)=0
(x+3)(x-3)(x+3)(x-3)=0
x-3=0 x=3
x+3=0 x=-3
(3,-3)

Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
There are 4 4th roots. You show 2 of them.
There are 2 square roots of 81, 9 and -9. Each of these has 2 square roots. 3 and -3 are the square roots of +9.
The other 2:

Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)

Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

The discriminant -36 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.

In the field of imaginary numbers, the square root of -36 is + or - .

The solution is , or
Here's your graph:

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