Respuesta :

Combining like terms are simply solving variable to variable and constant to constant, (15x - 0)  FINAL ANSWER x = 0
You would combine like terms for 12x + 5 +3x - 5 like this:

12x + 3x = 15x
5 - 5 = 0

So the answer to this problem is 15x + 0 or 15x.