How do I calculate this:

How do I solve/find the X value step by step of the equation in the website:

http://www.wolframalpha.com/input/?i=%281%2Fsqrt%28-x%29%29-%288%2Fx%5E2%29%3D0

1 / sqrt(-x) - 8/x^2 = 0

Move the second term to the other side:

1 / sqrt(-x) = 8 / x^2

Square both sides:

1 / -x = 64 / x^4

Cross multiply:

x^4 = -64x

Move the right term back over:

x^4 + 64x = 0

Factor:

x * (x^3 + 64) = 0

So, x = 0 is a solution, BUT the original equation has 0 as an asymptote, so this cannot be a solution. The other term gives:

x^3 + 64 = 0

Move the 64 over:

x^3 = -64

Take the cube-root:

x = -4