The right function is f(x)=3x^3-10x^2-81x + 28
You can realize that 7 is a root because it is in all the answers.
So you can divide the polynomial by x - 7. If you do it you can find that the quotient is 3x^2 + 11x - 4
Now you can use the quadratic formula to find the other two roots.
If you do it, you will find they are x = 1/3 and x = -4.
So the answer is option A) 7, -4, 1/3
And the polynomial can be written as (x - 7)(x + 4) (x -1/3)
