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

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

% NDG: points C and O are not the same

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

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

% DET: points C and A must be different

Using the point H_b and the line b, construct a line h_b (rule W10b);

Using the circle k(O,C) and the line h_b, construct a point B_k and a point B (rule W04);

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