6x⁴ - 9x³ - 36x ² + 54x can be rewritten as:
3x(2x³ - 3x² - 12x + 18) =
3x ((2x³ - 3x²) - 6(2x - 3)) =
3x (x²(2x - 3) - 6(2x - 3)) =
3x ((2x- 3)(x² - 6))
Finally, 3x(2x- 3)(x² - 6) is the factored form of expression 6x⁴ - 9x³ - 36x ² + 54x
Good luck.