Answer:
[tex]\frac{1}{y^{9} }[/tex]
Step-by-step explanation:
Using the rule of exponents
[tex]a^{-m}[/tex] ⇔ [tex]\frac{1}{a^{m} }[/tex] , then
[tex]y^{-9}[/tex] = [tex]\frac{1}{y^{9} }[/tex]
