Given: The polynomial function (X+3)(X+9)(X-6) = 0
We shall test above function with the given values of zeros as - 9, - 6, - 3, 0, +9, + 6, +3
For the given polynomial function (X+3)(X+9)(X-6) = 0, their zeros can be calculated as
either, (X+3)= 0, for this X = - 3
or, (X+9) = 0, for this X = - 9
or, (X-6) = 0, for this X = +6
Hence, the zeros of the given polynomial will be -3, +6 and -9 only