Move to the denominator using the negative exponent rule .

Move to the denominator using the negative exponent rule .

Multiply by by adding the exponents.

Move .

Use the power rule to combine exponents.

Add and .

Multiply by by adding the exponents.

Move .

Use the power rule to combine exponents.

Add and .

Factor out of .

Cancel the common factors.

Factor out of .

Cancel the common factor.

Rewrite the expression.

Simplify (12a^-9b^-4)/(9a^2b^6)