Final answer:
In the expression (-4) 5, -4 is used as a factor 5 times.
Step-by-step explanation:
To find out how many times -4 is used as a factor in the expression (-4) 5, we need to repeatedly multiply -4 by itself 5 times. This can be written as (-4) × (-4) × (-4) × (-4) × (-4). When we multiply two negative numbers, the result is positive, so each multiplication will result in a positive value. Therefore, -4 is used as a factor 5 times in the expression.