Distribute sum groups
x(x^2 + 4x - 2) - 5(x^2 + 4x - 2)
Distribute
x^3 + 4x^2 - 2x - 5(x^2 + 4x - 2)
Distribute
x^3 + 4x^2 - 2x - (5x^2 + 20x - 10)
Simplify brackets
x^3 + 4x^2 - 2x - 5x^2 - 20x + 10
Collect like terms
x^3 + (4x^2 - 5x^2) + (-2x - 20x) + 10
Simplify
x^3 - x^2 - 22x + 10