Question 753648
I understand that these are two separate problems.
3x - 5 = 7
    3x = 7 + 5
    3x = 12
     x = 12/3
     x = 4

3x/2 = 3
Multiply both sides by 2
 3x = 6
   x = 6/3
   x = 2

To check you can always put the answers
back into the original equations:-
3x - 5 = 7
3*4 - 5 = 7
12 - 5 = 7  which is correct
3x/2 = 3
3*2/2 = 3
6/2 = 3     which is correct.
Hope this helps
:-)