Colouring one side of a rectangle defined by \draw

Question

I create a rectangle like this:

\draw (2,2) -- (2,4) -- (6,4) -- (6,2) -- (2,2);

I would like to give the red colour to the side defined by points (2,2) and (2,4).

I tried doing

\draw [red] (2,2) -- (2,4) -- (6,4) -- (6,2) -- (2,2);

but this colours the entire rectangle.

Answer 1

there may be other ways but just splitting in to two is a simple possibility:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw [red] (2,2) -- (2,4);
\draw (2,4) -- (6,4) -- (6,2) -- (2,2);
\end{tikzpicture}
\end{document}

Answer 2

Another option: draw the rectangle and overwrite in red the side you want.

\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw (2,2) rectangle (6,4);
\draw [red] (2,2) -- (2,4);
\end{tikzpicture}
\end{document}