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

% NDG: points H_b and M_a are not the same

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

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

Using the point C and the point H_b, construct a line b (rule W02);

% DET: points C and H_b are not the same

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