numRegion[expr_,var_Symbol:x,range:{xmin_,xmax_}:{0,0},opts:OptionsPattern[]]:=Module[{le=LogicalExpand[Reduce[expr,var,Reals]],y,opendots,closeddots,max,min,len},opendots=Cases[Flatten[le/.And|Or->List],n_<var|n_>var|var<n_|var>n_:>n];
closeddots=Cases[Flatten[le/.And|Or->List],n_≤var|n_≥var|var≤n_|var≥n_:>n];
{max,min}=If[TrueQ[xmin<xmax],{xmin,xmax},{Max,Min}@Cases[le,_?NumericQ,Infinity]//Through];
len=max-min;
RegionPlot[le&&-1<y<1,{var,min-len/10,max+len/10},{y,-1,1},Epilog->{Thick,Red,Line[{{#,1},{#,-1}}]&/@closeddots,Dotted,Line[{{#,1},{#,-1}}]&/@opendots},Axes->{True,False},Frame->False,AspectRatio->.05,Ticks->{{{1.1,Subscript[-r,B]},{1.2,Subscript[-r,B]+δ},{1.84,Subscript[-r,0]-δ}},{}},AxesLabel -> {u,0}opts]]

numRegion[y<1.15||1.2≤y≤1.84,y]