Question 418946

12x^5 + 16x^4 -28x^3

= 4x^3(3x^2 + 4x -7)

now, factorize:  3x^2 + 4x -7

= 3x^2 + 7x -3x -7

= x(3x + 7) -1(3x +7)

= (x-1)(3x+7)


so, answers :   4x^3 * (x-1) * (3x+7)