Using the point M_a and the point H_a, construct a line a (rule W02);

% DET: points M_a and H_a are not the same

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

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

Using the point H_a and the line a, construct a line h_a (rule W10b);

Choose freely a point A on the line h_a (rule WOnline2)