theorem ThMak5:
  for S being (TE) (SC) (FS') TarskiGeometryStruct holds S is (RE')
  proof
    let S be (TE) (SC) (FS') TarskiGeometryStruct;
    let a,b,c,d be POINT of S;
    assume
A1: a <> b & between b,a,c;
    a,c equiv a,c & b,a equiv b,a & b,d equiv b,d by Satz2p1bis;
    hence thesis by A1,ThMak4;
  end;
