\input{preamble-standalone.ltx} \begin{document} % Ex. No. 27 (Section 6.1.2 : \IoptName{tkzDefTriangleCenter}{centroid}) \begin{tikzpicture}[scale=.75] \tkzDefPoints{-1/1/A,5/1/B} \tkzDefEquilateral(A,B) \tkzGetPoint{C} \tkzDefTriangleCenter[centroid](A,B,C) \tkzGetPoint{G} \tkzDrawPolygon[color=brown](A,B,C) \tkzDrawPoints(A,B,C,G) \tkzDrawLines[add = 0 and 2/3](A,G B,G C,G) \end{tikzpicture} \end{document}