Explanation:

The very first step that we will take is to transpose the equation 1 to have a numerical value on the right of the equality sign. We intend to factor the target expression with this transposed expression, x²−2x=−2.
Factoring this way we get expression,
E=x²(x²−2x)+2x³−x³+2x=x³−2x²+2x.
We have straightaway simplified the tail by using x²+2=2x for substitution.
So, E=x(x²−2x)+2x=−2x+2x=0