How do I solve:

-9x + 2x to the third power +8x -12x to the third power

Isn't there suppsed to be an "=" sign in there somewhere? If so, where?

You can't "solve" it if it isn't an equation.

-9x+2x=-7x

(-7x)^3=(-7)^3 *x^3=-343x^3

8x-12x=-4x

(-4x)^3=(-4)^3 *x^3=-64x^3

-343x^3 +(-64x^3)=
-343x^3-64x^3= -407x^3

To solve the expression -9x + 2x^3 + 8x - 12x^3, we need to simplify and combine like terms.

First, let's group the terms with the same exponent of x together:

-9x + 2x^3 + 8x - 12x^3

Grouping the above terms:

(2x^3 - 12x^3) + (-9x + 8x)

Combine the terms within each grouping:

-10x^3 - x

Therefore, the simplified form of the expression -9x + 2x^3 + 8x - 12x^3 is -10x^3 - x.