You're killing me!
7x7x7x7x7=?
Think about...
You are multiplying 7 five times. When use use an exponent your are simply showing the amount of time 7 (or whatever your number is) has been multiplied by itself in a more compact form.
For example:
5^8=5x5x5x5x5x5x5x5
Or
4x4x4=4^3
