\begin{tikzpicture} \clip (0,0) circle (2.3cm); \tkzDefPoint(0,0){O} \tkzDefPoint(2,0){A} \tkzDefPoint(.5,-.3){p} \tkzDefPoint(.7,.3){q} \tkzDrawCircle[dashed,color=blue](O,A) \tkzDefPoint(-.3,-0.25){z} \tkzDefPoint(-.8,-0.1){w} \tkzClipCircle(O,A) \tkzDrawCircle[orthogonal through=z and w](O,A) \tkzDrawCircle[orthogonal through=p and q](O,A) \draw (0,-2)--(0,2); \tkzDrawPoints[size=8,fill=red](O) \end{tikzpicture}