Multiplying out the equation (3x - 8)(2x^2 + 4x - 9) will get you;
6x^3 + 12x^2 - 27x - 16x^2 - 32x + 72
Combine like terms;
6x^3 - 4x^2 - 59x + 72
So the coefficient for the x^3 is 6.
The coefficient for the x^2 is -4.
The coefficient for the x is -59.