# What is the domain and range of f (x) = -2x + 6?

Because there are no restrictions on the value $x$ can be, then the domain of the function is the set of Real numbers: $\left\{\mathbb{R}\right\}$
The function is a linear transformation of $x$ and therefore the domain is also the set of Real numbers: $\left\{\mathbb{R}\right\}$