Answer:
If the base and the negative exponent is in the denominator already
Explanation:
Normally, a base with a negative exponent moves to the denominator.
Example: (2^-3 = 1 / (2)^3 = 1/8)
However, if the base and the negative exponent is already in the denominator, the base would move to the numerator and the exponent would become positive.
Example: 2 / (3)^-3 = 2 * 3^3 = 2 * 27 = 54