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

Choose freely a point A on the line b (rule WOnline1)

Using the point A, the point C, the point T_b and the line b, construct a point T`_b (rule W19);

% NDG: points A and C are not the same points C and T_b are not the same points C and midpoint([A,T_b]) are not the same

Choose freely a point B on the circle k_over(T_b,T`_b) (rule WOncircle)