[tex]f(x)=\dfrac{x-4}{x^2+5x-36}\\\\The\ domain:\\\\x^2+5x-36\neq0\\\\x^2+9x-4x-36\neq0\\\\x(x+9)-4(x+9)\neq0\\\\(x+9)(x-4)\neq0\iff x+9\neq0\ \wedge\ x-4\neq0\\\\x\neq-9\ \wedge\ x\neq4\\\\Answer:\ x\in\mathbb{R}-\{-9,\ 4\}\to x\in(-\infty,\ -9)\ \cup\ (-9,\ 4)\ \cup\ (4,\ \infty)\\\\\to x\neq-9\ \wedge\ x\neq4[/tex]