Thank you for the opportunity to help you with your question!

f(x)=(x-1)/(5x+9)

= 5x^2 +9x - 5x -9

= 5x^2 + 4x - 9

domain is of a function is the set of "input" or argument values for which the function isdefined. That is, the function provides an "output" or value for each member of the domain.

here we can see that there is a defined output value for any input value,x.

so the domain of the function includes all real numbers which can be represented as

domain of f(x) = ( -∞ ,+ ∞)....................................ANSWER

Please let me know if you need any clarification. I'm always happy to answer your questions.