First you would do 5-2.
That would give you 3(x-1)=12
Next, 3 would be distributed into x-1
That would give you 3x-3=12
After that, you add 3 on both sides of the equal sign.
That would give you 3x=15
Finally, divide 3 on both sides and your final answer is:
x=5
If you do a Check, 12 will equal 12.
Hope this helps!!!