Answer
$(-\infty, 4)$
Refer to the image below for the graph.
Work Step by Step
Subtract 1 from each side of the inequality to obtain:
$\begin{array}{ccc}
&x+1-1 &\lt &5-1
\\&x &\lt &4
\end{array}$
Thus, the solution set is $(-\infty, 4)$.
To graph this on a number line. plot a hollow dot at $4$, then shade the region to its left.
