Using the point H_c and the point M_b, construct a circle k(M_b,C) (rule W06);

% NDG: points H_c and M_b are not the same

Choose freely a point A on the circle k(M_b,C) (rule WOncircle)

Using the point A and the point M_b, construct a point C (rule W01);

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

% DET: points A and H_c are not the same

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