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

% DET: points H_a and T_a are not the same

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)

Using the point A and the point T_a, construct a line s_a (rule W02);

% DET: points A and T_a are not the same

Using the point H_a, the point A, the point T_a, the line s_a and the line h_a, construct a line AO (rule W17);

% NDG: points A and T_a are not the same points H_a and A are not the same

% DET: points A and T_a are not the same

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

Using the point B and the point A, construct a point M_c (rule W01);

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

% DET: points B and A are not the same

Using the point M_c and the line c, construct a line m_c (rule W10b);

Using the line m_c and the line AO, construct a point O (rule W03);

% NDG: lines m_c and AO are not parallel

% DET: lines m_c and AO are not the same

Using the point B and the point O, construct a circle k(O,C) (rule W06);

% NDG: points B and O are not the same

Using the circle k(O,C), the line a, the point O and the point B, construct a point C (rule W05);

% NDG: line a and circle k(O,C) intersect

% DET: points B and C must be different