 \begin{tikzpicture}[scale=1.2,rotate=-90]
 \tkzInit
 \tkzDefPoint(0,0){A} \tkzDefPoint(5,0){B}
 \tkzDrawSegment(A,B)
 \tkzDefPointBy[rotation= center A angle 60](B)
 \tkzGetPoint{C}
 \tkzDefPointBy[symmetry= center C](A)
 \tkzGetPoint{D}
 \tkzDrawSegment(A,tkzPointResult)
 \tkzDrawLine(B,D)
 \tkzDrawArc[delta=10](A,B)(C)
 \tkzDrawArc[delta=10](B,C)(A)
 \tkzDrawArc[delta=10](C,D)(D)
 \tkzMarkRightAngle(D,B,A)
\end{tikzpicture}
