Answer:
See below.
Explanation:
We are asked for a unknown number.
To find our number, we should use the Inverse Operation.
What is the Inverse Operation?
The Inverse Operation is the opposite operation.
For example: If we Multiplied, then we should use the Inverse Operation which is Dividing.
Let's divide 256 by -32 to identify our missing number.
Divide:

Our missing number is -8.