If f(x)=6x^3 - ax^2 + bx + c when a, b and c are constant when f(x) is divided by x^2 - 4 the remainder is 23x - 26. When f(x) divided by (x + 3) the remainder is -220. Find:

Question

If f(x)=6x^3 - ax^2 + bx + c when a, b and c are constant when f(x) is divided by x^2 - 4 the remainder is 23x - 26. When f(x) divided by (x + 3) the remainder is -220. Find:
(A) the value of a, b and c
(B) the solution of the equation f(x)=0