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

% DET: points A and H_a are not the same

Using the point H_a and the line h_a, construct a line a (rule W10a);

Using the point A, the line a and the point H_a, construct a line h_A,2/3(a) (rule W15);

Choose freely a point G on the line h_A,2/3(a) (rule WOnline4)

Using the point G and the point A, construct a point M_a (rule W01);

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);