Question

How do you factor `-4x^4+8x^3-20x`?

Answer 1

`-4x(x^2(x-2)+5)`

Explanation:

Look for anything that can be factored from everything like a `-4x`
so `-4x^4+8x^3-20x` becomes `-4x(x^3-2x^2+5)`

At this point look to see if `x^3-2x^2+5` can be factored, it looks like an `x^2` can be taken from `x^3-2x^2` which becomes: `x^2(x-2)`

This gives the final answer:
`-4x(x^2(x-2)+5)`