Answer:
3, 6, 4, 5 
Step-by-step explanation:
First of all we have to multiply 2 by 2x and -9 and we obtain 
4x -18 ≤ 6 
now we have to move -18 on the right side of the minor or equal and change its sign 
4x ≤ 6 + 18 
now we have to added up 6 and 18 
4x ≤ 24 
At least we have to divide the the two members by 4 
x ≤ 6 
We have to find the numbers ≤ 6 
so the answer is : 3, 6, 4, 5