Answer:

Explanation:
Start by making a common denominator. In this case, it would be 12.
Multiply -1/3 by 4 to get -4/12
Multiply -9/4 by 3 to get -27/12
Then subtract
-
- (-
) =23/12
You can also visualize this on a number line. Once you've made the denominator the same, start at -4/12 and move 27 units to the left to land on 23/12.