Answer:
1, 2, 3, 6
Explanation:
The given equation is,


We need to to find all the whole values of a for which the solution of the equation i.e x will be a whole number.
We know that when a number is divided by one of its factor it leaves a remainder of 0 or the result we get is a whole number.
That is why, we need a as one of the factors of 6, i.e 1, 2, 3, 6 in order to get x as a whole number.