# How do you find the domain of f(x)=3x+6?

Jun 7, 2018

Domain $\left\{x | x \text{ is } \mathbb{R}\right\}$ or in interval notation $\left(- \infty , \infty\right)$
$f \left(x\right) = 3 x + 6$ is the equation of a line, there are no restrictions of input on any lines so the domain is all real numbers.
Domain $\left\{x | x \text{ is } \mathbb{R}\right\}$ or in interval notation $\left(- \infty , \infty\right)$