\documentclass{article}

\usepackage{pgfplots}

\pgfplotsset{compat=1.6}

\begin{document}

\begin{tikzpicture}
	\begin{axis}[
		title=false,
		axis equal,
		unit rescale keep size=false,
	]
	\addplot coordinates {(0,-3) (1,3)};
		
	\end{axis}
\end{tikzpicture}

\end{document}

