# How do you find the domain and range of k(x)=9 ?

Jun 12, 2017

Determine all possible values the function can have. In this case, it is $\text{D} : \left\{x \in \mathbb{R}\right\}$ and $\text{R} : \left\{y \in \mathbb{R} | 9\right\}$.

#### Explanation:

This is a linear function; a straight line.

In addition, this is a horizontal straight line. I know this because the degree is $1$, and there are no other variables.

Domain and range are sets of all possible values the function can have (may not be at the same time).

Because the function is a straight line at the $\left(x , 9\right)$, the domain is limitless unless context is given to restrict the function. The range however, is only at $\left(x , 9\right)$.

Therefore, the domain and range are:

$\text{D} : \left\{x \in \mathbb{R}\right\}$
$\text{R} : \left\{y \in \mathbb{R} | 9\right\}$

Unfortunately, Socratic cannot graph functions of horizontal/vertical straight lines... but just imagine a horizontal straight line at the $\left(x , 9\right)$.

Hope this helps :)