\documentclass[varwidth=true, border=10pt]{standalone}
\usepackage{tkz-euclide}
\usepackage{tkz-fct}
\newcommand{\iu}{{i\mkern1mu}} % imaginary unit

\begin{document}
\usetkzobj{all}
\begin{tikzpicture}
    \tkzSetUpPoint[shape=circle,size=3,color=black,fill=black]
    \tkzSetUpLine[line width=0.5]
    \tkzInit[xmax=4.5,ymax=3,xmin=-1,ymin=0]
    \tkzDefPoints{0/0/O, 3/3/lz, 2/2/z, 3/0/lzx, 2/0/zx}
    \tkzDrawLines(O,lz zx,z)
    \tkzDrawLine[add=0 and 0.2](lzx,lz)
    \tkzAxeXY[ticks=false]

    %\tkzDrawArc[R,line width=1pt,color=red](m1,1.5 cm)(0,180)
    %\tkzDrawArc[R,line width=1pt](m2,2.5 cm)(0,180)
    \tkzDrawPoints(z,lz)
    \tkzLabelPoint[left](z) {$z$}
    \tkzLabelPoint[above right](zx) {$x$}
    \tkzLabelPoint[right](lz) {$\lambda^2 z$}
    \tkzLabelPoint[above right](lzx) {$\lambda^2 x$}
    %\node[red] at ($(m1)+(1.5,-0.2)$)  {$m+1$};
\end{tikzpicture}
\end{document}