Hello, thank you for taking the time to post your question!
12 – (x + 2) = 8 is the expression because it’s saying that when the sum of the number (x) and 2 is subtracted from 12, the result is 8
From there then you want to solve for the value of “x” algebraically
12 – x – 2 = 8
10 – x = 8
-x = -2
x = 2
I hope that helps you get moving in a better direction on this type of question! Feel free to reach out if you have any additional questions beyond that :)