reserve a,a1,a2,a3,b,b1,b2,b3,r,s,t,u for Real;
reserve n for Nat;
reserve x0,x,x1,x2,x3,y0,y,y1,y2,y3 for Element of REAL n;
reserve L,L0,L1,L2 for Element of line_of_REAL n;
reserve P,P0,P1,P2 for Element of plane_of_REAL n;

theorem Th106:
  L1 // L2 & L1 <> L2 implies ex P st L1 c= P & L2 c= P & P is being_plane
proof
  assume that
A1: L1 // L2 and
A2: L1 <> L2;
A3: L2 is being_line by A1,Th66;
  L1,L2 are_coplane & L1 is being_line by A1,Th66,Th97;
  hence thesis by A1,A2,A3,Th71,Th98;
end;
