documentclass[12pt,border=5pt]{standalone}
usepackage{newcent,pstricks,pst-eucl,amsmath,amssymb}
usepackage{auto-pst-pdf}
begin{document}

begin{pspicture}
psset{PointSymbol=o}
pstGeonode[PointName=none,PointSymbol=none](2,4){A}(0,0){B}(6,0){C}
pstCircleABC[PosAngle=180]{A}{B}{C}{O}
pstGeonode[PosAngle=60](10,2){M}
pstMiddleAB[PointName=none,PointSymbol=none]{O}{M}{M'}
pstInterCC[DiameterB=pstDistAB{O}{M},PosAngleA=45,
 PosAngleB=-45]{O}{A}{M'}{}{D}{E}
{psset{nodesepB=-1}
pstLineAB{M}{D} pstLineAB{M}{E}}
ncLine{O}{D} ncLine{O}{E}
pstInterLL[PointSymbol=none,PosAngle=50,PointNameSep=.55]{O}{M}{D}{E}{H}
pstRightAngle[RightAngleSize=.2]{D}{H}{M}
ncLine{O}{M} ncLine{D}{E}
end{pspicture}
end{document}