theorem Th44: :: BKMODEL2:58
for P, Q being Element of BK_model st P <> Q holds
ex P1, P2, P3, P4 being Element of absolute ex P5 being Element of (ProjectiveSpace (TOP-REAL 3)) st
( P1 <> P2 & P,Q,P1 are_collinear & P,Q,P2 are_collinear & P,P5,P3 are_collinear & Q,P5,P4 are_collinear & P1,P2,P3 are_mutually_distinct & P1,P2,P4 are_mutually_distinct & P5 in (tangent P1) /\ (tangent P2) )