## College Algebra (10th Edition)

We know that if a function is odd, then $f(-x)=-f(x).$ We know that if a function is even, then $f(-x)=f(x).$ Hence we plug in $-x$ to see what happens. $f(-x)=\frac{5(-x)}{(-x)^2-9}=\frac{(-5x)}{x^2-9}.$ Therefore the function is odd.