how to factor by grouping to factor 4x^3+12^2-9x-27
4x³ + 12x² - 9x - 274x²(x) - 4x²(3) + 9(x) - 9(3)4x²(x - 3) + 9(x - 3)(4x² + 9)(x - 3)
4x³+12x²-9x-274x²(x)+4x²(3)-9(x)-9(3)4x²(x+3)-9(x+3)(4x²-9)(x+3)(2x-3)(2x+3)(x+3)