Answer:
8.5-5.7n-4b
Explanation:
Variable- x, y, or in your case n and b
1. You can't subtract or add numbers with a different variable. For example you can't do 4b-3a so you can't so 5.7n-4b.
2. If there are numbers without variables do them first. 2.5+6=8.5
3. Now since you can't subtract those numbers with variables you right your final equation. Start with your answer that replaces 2.5- 8.5 Then you see put down- 5.7n- 8.5-5.7n Then lastly you have- 4b- 8.5-5.7n-4b