Here, we want to find the result of (f-g)(x)
What we simply want to here is to subtrcat g(x) from f(x)
We proceed as follows;
[tex]\begin{gathered} f(x)=x^2-13x\text{ + 36} \\ \\ g(x)\text{ = x - 9} \\ \\ (f-g)(x)\text{ = f(x) - g(x)} \\ \\ (f-g)(x)=x^2-13x\text{ + 36 - (x - 9)} \\ \\ (f-g)(x)=x^2-13x\text{ + 36 - x + 9} \\ \\ (f-g)(x)=x^2-13x-x\text{ + 36 + 9} \\ \\ (f-g)(x)=x^2-14x+\text{ 45} \end{gathered}[/tex]