Answer:
8x + 9
Step-by-step explanation:
Combine 6x and 2x since they are "like variables" meaning they both contain an x, and write in standard form ax + bx + c
Step-by-step explanation:

He would be 15 years old depending on his birthday if he has a late birthday he would be 14 years and if he had a early birthday he would be 16 years old