Answer:
[tex]\huge\boxed{x\neq4\to x\in\mathbb{R}\backslash\{4\}}[/tex]
Step-by-step explanation:
[tex]\dfrac{x-3}{2x-8}[/tex]
We know: the denominator must be different than 0.
Therefore
[tex]2x-8\neq0[/tex] add 8 to both sides
[tex]2x-8+8\neq0+8[/tex]
[tex]2x\neq8[/tex] divide both sides by 2
[tex]\dfrac{2x}{2}=\dfrac{8}{2}\\\\x\neq4[/tex]