Treat this as any other inequality and focus on getting the x by itself.
First add 6 to everything to eliminate the -6 in the middle:
-4 + 6 ≤ 2x-6 + 6 ≤ 12 + 6
- 2 ≤ 2x < 18
Then divide everything by 2 to get the 2 off the 2x.
-2 / 2 ≤ 2x / 2 ≤ 18/2
- 1 ≤ x ≤ 9
