reserve AS for AffinSpace,
  a,b,c,d,p,q,r,s,x for Element of AS;
reserve AFP for AffinPlane,
  a,a9,b,b9,c,c9,d,p,p9,q,q9,r,x,x9,y,y9,z for Element of AFP,
  A,C,P for Subset of AFP,
  f,g,h,f1,f2 for Permutation of the carrier of AFP;

theorem Th7:
  AFP is translational implies ex f st f is translation & f.a=b
proof
  assume
A1: AFP is translational;
  a=b implies thesis by Th5;
  hence thesis by A1,Lm12;
end;
