reserve X,Y for set;
reserve R for domRing-like commutative Ring;
reserve c for Element of R;
reserve R for gcdDomain;

theorem
  for F be add-associative right_zeroed right_complementable Abelian
    distributive non empty doubleLoopStr,
      x,y being Element of F holds
    (-x)*y = -x*y & x*(-y) = -x*y by VECTSP_1:8,9;
