Respuesta :

Answer:

4x is the answer

Step-by-step explanation:

3x + x= 4x + x = 5x - x = 4x

168136

Answer: 3+x

Step-by-step explanation: Variables cannot mix with non-variables so x-x = 0x. 0x + x = x. x +3 = 3+x or x+3. Brainliest please?