%% 
%%  A DANTE-Edition example
%% 
%%  Example 29-01-6 on page 555.
%% 
%%  Copyright (C) 2011 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{129.70511pt}
\setlength\parindent{0pt}

\usepackage{pst-eucl}

\begin{document}
\begin{pspicture}(-1.5,-1.5)(1.5,1.5)
  \psset{SegmentSymbol=pstslash}
  \pstTriangle[PosAngleB=90, PosAngleC=180,
    linecolor=blue,linewidth=.5\pslinewidth]
    (1.5,-1){A}(0,1){B}(-1,-.5){C}
  \psset{SegmentSymbol=pstslash}
  \pstSegmentMark{A}{B} \pstSegmentMark{A}{C}
  \pstSegmentMark[SegmentSymbol=MarkCross]{C}{B}
\end{pspicture}
\end{document}