Answer:
a straight line: y = x -5, with a hole at (4, -1)
Step-by-step explanation:
The rational function can be simplified to ...
[tex]f(x)=\dfrac{x^2-9x+20}{x-4}=\dfrac{(x-5)(x-4)}{(x-4)}\\\\f(x)=x-5\qquad\text{$x\ne 4$}[/tex]
The graph of this is a straight line, with a hole at x=4, where the function is not defined.
