Improper Integral 1

Calculus Level 4

Given that \(\displaystyle \int _{ a }^{ \infty }{ \frac { { e }^{ x } }{ { 9e }^{ 2x }+64 } dx=\frac { \pi }{ K } } \), where \(a=\ln { \left(\frac { 8\sqrt { 3 } }{ 3 } \right) } \), what is the value of \(K\)?