x - 3 = 7
1. You would first add 3 to 3 as the negative subtraction operation sign makes it a negative and you have to get rid of it.
- 3 + 3
2. Whatever you do to one side, you have to do it to the other side too. As a result, you would add 3 to 7 and you would get 10.
This is what your equation should look like after:
x = 10
That is how you isolate the variable by using the one-step equation method