Using the point H_c and the point M_a, construct a circle k(M_a,B) (rule W06);

% NDG: points H_c and M_a are not the same

Choose freely a point B on the circle k(M_a,B) (rule WOncircle)

Using the point B and the point M_a, construct a point C (rule W01);

Using the point B and the point H_c, construct a line c (rule W02);

% DET: points B and H_c are not the same

Choose freely a point A on the line c (rule WOnline1)