Answer:
- -10 < n < 8
- 5/4 < x ≤ 6
Step-by-step explanation:
1. Subtract 9:
-10 < n < 8
__
2. Add 12, then divide by 8:
10 < 8x ≤ 48
10/8 < x ≤ 6
5/4 < x ≤ 6 . . . . . with the fraction reduced
_____
The rules of equality allow us the do these operations, provided that we do them to all parts of the compound inequality. That is, when we say "subtract 9", we mean ...
-1 -9 < 9 +n -9 < 17 -9
This simplifies to the inequality we show above:
-10 < n < 8
