Answer:
x = 1/3
Explanation:
First, you have to combine like terms so 10x -x is 9x. Now we have a new equation.
9x + 9 = 12
We're going to have to solve for the digits without variables like so,
9x + 9 = 12
-9 -9
9x = 3
All we've got left here is to isolate the variable and to do that you divide both sides by 9.
x = 3/9 and 3/9 is the same as 1/3
Hope this helps and have a great day!