Answer:
10b
Step-by-step explanation:
The letter b is a variable in this equation, and variables dont change when you add/subtract numbers with the same variable on them. So it turns into really 7+4-1. You would follow the rules of PEMDAS and just go left to right, so you add 7 and 4 to get 11, then subtract one to get ten. Then you have 10b.
