reserve a,b,c,d for Real;
reserve r,s for Real;

theorem Th82:
  b < 0 & a*b < c implies c/b < a
proof
  assume that
A1: b<0 and
A2: a*b<c;
  a*b/b>c/b by A1,A2,Lm29;
  hence thesis by A1,XCMPLX_1:89;
end;
