overleaf subfigures
\begin{figure}
\centering
\begin{subfigure}[b]{0.3\textwidth}
\centering
\includegraphics[width=\textwidth]{graph1}
\caption{$y=x$}
\label{fig:y equals x}
\end{subfigure}
\hfill
\begin{subfigure}[b]{0.3\textwidth}
\centering
\includegraphics[width=\textwidth]{graph2}
\caption{$y=3sinx$}
\label{fig:three sin x}
\end{subfigure}
\hfill
\begin{subfigure}[b]{0.3\textwidth}
\centering
\includegraphics[width=\textwidth]{graph3}
\caption{$y=5/x$}
\label{fig:five over x}
\end{subfigure}
\caption{Three simple graphs}
\label{fig:three graphs}
\end{figure}