Using the point B and the point H_b, construct a line h_b (rule W02);

% DET: points B and H_b 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 point H_b and the line h_b, construct a line b (rule W10a);

Using the circle k(O,C) and the line b, construct a point C and a point A (rule W04);

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