Hi! I'm happy to help!
To solve this problem, we need to first solve .
Negative exponents divide the number by x instead of multiplying. So, is 1/625. Since we can't use another negative exponent, we can use a number that would decrease with a positive exponent. In this situation, we can use the inverse of 5, which is , and put this to the fourth power.
This expression also equals 1/625.
I hope this was helpful, and keep learning! :D