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

% Ex. No. 147 (Section 18.1.8 : Spieker circle with option \tkzname{spieker})

\begin{tikzpicture}[scale=1]
  \tkzDefPoints{ 0/0/A,4/0/B,0.8/4/C}
   \tkzDefSpcTriangle[medial](A,B,C){M_a,M_b,M_c}
   \tkzDefTriangleCenter[spieker](A,B,C)
   \tkzGetPoint{S_p}
   \tkzDrawPolygon[blue](A,B,C)
   \tkzDrawPolygon[red](M_a,M_b,M_c)
   \tkzDrawPoints[blue](B,C,A)
   \tkzDrawPoints[red](M_a,M_b,M_c,S_p)
   \tkzDrawCircle[in,red](M_a,M_b,M_c)
   \tkzAutoLabelPoints[center=S_p,dist=.3](M_a,M_b,M_c)
   \tkzLabelPoints[blue,right](S_p)
   \tkzAutoLabelPoints[center=S_p](A,B,C)
\end{tikzpicture}

\end{document}