Answer: {1, 2, 3, 4}
==========================================================
Step-by-step explanation:
The tri-inequality A < B < C breaks up into A < B and B < C
Use this idea to break up 2 ≤ 2x < x+5 into these two pieces
We'll solve each inequality individually.
Let's start with the first one.
2 ≤ 2x
2/2 ≤ 2x/2
1 ≤ x
Now onto the second inequality
2x < x+5
2x-x < x+5-x
x < 5
-------------------------
From here recombine 1 ≤ x and x < 5 to get 1 ≤ x < 5
If x is an integer only, then the roster set of solutions that satisfy this inequality is {1, 2, 3, 4}. Notice 5 is not part of the solution set, but 1 is.
We can replace x with any of those items in bold to get a true statement.
For instance, let's replace x with 3.
1 ≤ x < 5 updates to 1 ≤ 3 < 5 which is true
Let's go back to the original tri-inequality and replace each x with 3. Then simplify each side.
2 ≤ 2x < x+5
2 ≤ 2*3 < 3+5
2 ≤ 6 < 8
We end up with a true statement, which verifies that x = 3 is one of the integer solutions. I'll let you verify the other values 1,2, and 4.