Don't worry, there are only eight more rules.  Heh -- just kidding.  There are only a few more.  This one is just a little notation trick.

w^(-3)can be rewritten as1 / w^3

1 / x^(-2)can be rewritten asx^2

This is a trick that works just for negative exponents!

Let's look at these as fractions...

w^(-3) / 1 = 1 / w^3and1 / x^(-2) = x^2 / 1

Anytime a guy with a negative exponent gets moved over the fraction line, the sign turns positive.

Here are the official rules:

Exponent Rule #4:  1 / a^(-n) = a^nandExponent Rule #4:  a^(-n) = 1 / a^n