theorem
  {p7 where p7 is Point of TOP-REAL 2: -p7`1<=p7`2 } is closed Subset of
  TOP-REAL 2 & {p7 where p7 is Point of TOP-REAL 2: p7`2<=-p7`1 } is closed
  Subset of TOP-REAL 2 by Lm11,Lm14;
