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

% DET: points B and C are not the same

Using the point C and the point T_b, construct a line b (rule W02);

% DET: points C and T_b are not the same

Using the point T_b and the line a, construct a circle k(T_b,foot[T_b,c]) (rule W11);

% NDG: point T_b is not incident to the line a

Using the circle k(T_b,foot[T_b,c]), the point B, the point T_b and the line a, construct a line c (rule W13);

% NDG: point B is outside the circle k(T_b,foot[T_b,c])

Using the line c and the line b, construct a point A (rule W03);

% NDG: lines c and b are not parallel

% DET: lines c and b are not the same