For what valve of k is the following function continuous at

For what valve of $k$ is the following function continuous at $x=2$

$f(x)=\left\{\begin{array}{r}2 x+1, \text { when } x<2 \\ k, \text { when } x=2 \\ 3 x-1, \text { when } x>2\end{array}\right.$