If I am reading the equations correctly, they are:
5x - 14 = 3x AND 7x + 12 = x - 6
If this is correct, the first one would be worked out like this:
5x (- 5x) - 14 = 3x (- 5x)
- 14 = - 2x
- 14 (/ - 2) = - 2x (/ - 2)
7 = x
The second would be worked out like this:
7x + 12 (+ 6) = x - 6 (+ 6)
7x + 18 = x
7x (- 7x) + 18 = x (- 7x)
18 = - 6x
18 (/ - 6) = - 6x (/ - 6)
- 3 = x
I hope this is what you are looking for :)