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

% Ex. No. 81 (Section 15.1.1 : Example with point references)

\begin{tikzpicture}[scale=1.5]
  \tkzDefPoint(0,0){A}
  \tkzDefPoint(2,1){B}
  \tkzDrawSegment[color=red,thin](A,B)
  \tkzDrawPoints(A,B)
  \tkzLabelPoints(A,B)
\end{tikzpicture}

\end{document}
