The Cartesian graph of an affine function is the translation of a line that represents a direct variation function.

### Examples

The function *f* : \(\mathbb{R}\) → \(\mathbb{R}\) : *x* ↦ 2*x* + 1 is an affine function.

The function *f* : \(\mathbb{R}\) → \(\mathbb{R}\) : *x* ↦ 3*x* also is an affine function, although it is generally called a linear function or a direct variation function. In this case, parameter b has a value of zero.