Negative Exponent Rule: Negative exponents in the numerator get moved to the denominator and become positive exponents. Negative exponents in the denominator get moved to the numerator and become positive exponents. Only move the negative exponents.becomes: Warning!: Don't do that if the expressions with the negative exponents are added or subtracted, or are factors of something added or subtracted. You can't follow that rule with: So don't try!. Just use the rule when the negative exponentials are only multiplied or are factors of something multiplied (not added or subtracted). Edwin