Horizontal line test

Plot[{
(x^2),
0.5
},{x,-1,1}
,PlotLegends->{"(x^2)", "y=0.5"}
,Epilog->{
PointSize[Large],
Point[{{-(Sqrt[0.5]),0.5},{(Sqrt[0.5]),0.5}}]
}
]

Plot[{
(x^2)+I UnitStep[-x],
0.5
},{x,-1,1}
,PlotLegends->{"(x^2)(Subscript[|, x ≥ 0])", "y=0.5"}
,Epilog->{
PointSize[Large],
Point[{{(Sqrt[0.5]),0.5}}]
}
]

Plot[{
(2^x),
2
},{x,-2,2}
,PlotLegends->{"(2^x)","y=2"}
,Epilog->{
PointSize[Large],
Point[{{1,2}}]
}
]

Plot[{
(2^x),
(2^(-x)),
(2^x)+(2^(-x))
}, {x,-2,2}
,PlotRange->{Full,{0,All}}
,PlotLegends->"Expressions"
]

Reduce[Abs[x]-1>2x+2,Reals]

Reduce[y>(Sqrt[x-2]), Reals]