First, we have to solve this inequality. The first step to doing this is to add 10 on all sides of the inequality:
Next, divide all sides by 2 and your inequality is:
In set notation, this inequality is 5 ≤ x ≤ 8.
Next, interval notation has the endpoints of the line, with brackets meaning that the endpoint is included while parentheses mean the endpoint is not included. (example: (-2,18] . -2 is not included, 18 is included.) Looking at our inequality, the interval notation is [5,8].
Lastly, referring back to the inequality once more, the solution set that represents our inequality is C.