\input{preamble-standalone.ltx}
\begin{document}

% Ex. No. 103 (Section 14.4.1 : Marks for an isosceles triangle)

\begin{tikzpicture}[scale=1]
 \tkzDefPoints{0/0/O,2/2/A,4/0/B,6/2/C}
 \tkzDrawSegments(O,A A,B)
 \tkzDrawPoints(O,A,B)
 \tkzDrawLine(O,B)
 \tkzMarkSegments[mark=||,size=6pt](O,A A,B)
\end{tikzpicture}

\end{document}