The factor of the determinant
∣∣ ∣ ∣∣x52x294x3168∣∣ ∣ ∣∣ is (x - .......)
2
As explained in the factor theorem the value of the variable x which makes the determinant zero is called the factor of the determinant.
In the above question, we can see that if we put x=2 the elements of the first columns becomes 2, 4 and 8 which is same as the third column. And as we have seen before, when two rows or columns are same the value of the determinant is 0. So (x-2) is the factor of the above determinant.