\documentclass[12pt]{article}

\usepackage{pstricks} % To use the standard "xcolor" package with PSTricks
\usepackage{pst-node}
\usepackage{pst-plot}

\pagestyle{empty}

\begin{document}
\psset{unit=5mm,linewidth=.1}

\begin{center}
\begin{figure}
\begin{pspicture}(-5,5)(5,5) % -.3 due to the coordinates under Ox
\SpecialCoor

% \psaxes{->}(0,0)(-5,-5)(5,5)

\pspolygon[linestyle=none,fillcolor=green,fillstyle=solid](-0.6,0.7)(1.7,-0.4)(1.3,2.1)
\rput(1,1){\psframebox[linestyle=none]{?}}

\psline[linecolor=red,linestyle=dotted](-10,6)(-0.7,0.7)
\psline[linecolor=red](-0.7,0.7)(7,-3)

\psline[linecolor=red](0,10)(1.7,-0.3)
\psline[linecolor=red,linestyle=dotted](1.7,-0.3)(3.5,-10)

\psline[linecolor=red](-9,-5)(1.3,2.1)
\psline[linecolor=red,linestyle=dotted](1.3,2.1)(6,5)

\rput(-2,4){\psframebox[linecolor=white]{$\mathcal{R}_1$}}
\rput(0,-2){\psframebox[linecolor=white]{$\mathcal{R}_2$}}
\rput(3,1){\psframebox[linecolor=white]{$\mathcal{R}_3$}}

\psline[arrows=<->](-1,8)(2,8.5)
\rput(-2,8){\psframebox[linecolor=white]{$\mathcal{C}_1$}}
\rput(3,8){\psframebox[linecolor=white]{$\mathcal{C}_3$}}

\psline[arrows=<->](6,-1.5)(5,-3.5)
\rput(6,-0.5){\psframebox[linecolor=white]{$\mathcal{C}_2$}}
\rput(5,-4.5){\psframebox[linecolor=white]{$\mathcal{C}_3$}}

\psline[arrows=<->](-6.5,-1.5)(-5,-3.5)
\rput(-7.5,-1){\psframebox[linecolor=white]{$\mathcal{C}_1$}}
\rput(-5,-4.5){\psframebox[linecolor=white]{$\mathcal{C}_2$}}


\end{pspicture}
\end{figure}
\end{center}

\end{document}