2≤y-4<7

There are three parts to the equation:

2, y-4, and 7, all separated by in inequality sign (in the same category as an equal sign).

If you simply had: 2 ≤ y-4, you would add 4 to each side and end up with 6 ≤ y. When there are three parts to the equation, you simply add the 4 to all three parts to get your answer.

2+4 ≤ y-4+4 <7+4
Now you finish it. If you need to graph it, darken the section of the number line that matches your equation. Empty circle at the less than sign and a solid circle at the less than or equal to sign. :-)