Multi step variables I need a step by step or something

First distribute the 3 so you'll have:
12+12x=12x+12
Next you subtract 12 from both sides and you'll get:
12x=12x
then you divide both sides by 12 and you get:
x=x
Problem: 3(4+4x)=12x+12
The first thing that you need to do is distribute 3(4+4x).
12+12x=12x+12
Subtract 12x from both sides.
12=12
This means that the equation has infinitely many solutions.
I hope this helps you :)