# How do you find the domain and range of f(x)=2x+4?

Since the function is defined for all real $x$, we can conclude that the domain is just the real numbers, $D = \mathbb{R}$.
The values of the function go from $- \infty$ to $\infty$, and the function is continuous, which means that values can be all real numbers, so the range is also all real numbers, $R = \mathbb{R}$