Sorry, but there seems to be some confusion in your equations. It looks like some of them are incorrect or incomplete.

Let's try to solve the first equation:
2x - 9 = 12
Add 9 to both sides:
2x = 21
Divide by 2:
x = 10.5

For the second equation:
3x + 12 = 3427
Subtract 12 from both sides:
3x = 3415
Divide by 3:
x = 1138.3

It's not clear what you are trying to achieve with the other equations, but please let me know if you need any further assistance.