Simplify Express Final Results Using Positive Exponents Only $\left( \frac { x ^ { 8 } } { y ^ { 9 } } \right) ^ { - \frac { 1 } { 8 } }$

Simplify. Express final results using positive exponents only. $\left( \frac { x ^ { 8 } } { y ^ { 9 } } \right) ^ { - \frac { 1 } { 8 } }$