\input{preamble-standalone.ltx} \begin{document} % Ex. No. 138 (Section 17.10.1 : Option \tkzname{center}) \begin{tikzpicture} \tkzDefPoints{0/0/P0,0/0/Q0,2/0/P1} \tkzDefMidPoint(P0,P1) \tkzGetPoint{Q1} \tkzDefRegPolygon[center,sides=7](P0,P1) \tkzDefMidPoint(P1,P2) \tkzGetPoint{Q1} \tkzDefRegPolygon[center,sides=7,name=Q](P0,Q1) \tkzDrawPolygon(P1,P...,P7) \tkzFillPolygon[gray!20](Q0,Q1,P2,Q2) \foreach \j in {1,...,7} {\tkzDrawSegment[black](P0,Q\j)} \end{tikzpicture} \end{document}