Plot[x^2 + 5Cos[x] - Exp[x],{x,-5,5},PlotRange->{-20,20}]

ContourPlot[Sin[x*y] - x^2y^7 + 2Exp[2y-2]==2,{x,-1,1},{y,-0.5,3},ContourStyle->Thick,Axes->True,AxesOrigin->{0,0},Frame->None]
Export["FLevelSet.eps",%]