Question

(3 times X equal to 18 plus X

Answer 1

The answer is 9
because
3x=x +18
you take x from the right and what you do to one side you have to do to the other
So you are left with
2x=18
then you divide 18 by two and get x=9

Answer 2

Let's say x=9 so if we substitute it for x we would get both side equal.

3x=18+x

3(9)=18+9

27=27