In[]:=
$PreRead=(*replacesrank-2column-matrixvectorwithrank-1vector*)​​#/.RowBox[{"(",GridBox[{{a_},{b_}}],")"}]​​RowBox[{"{",RowBox[{a,",",b}],"}"}]&;​​​​​​​​crcChord5[{h_,k_},r_,line_]:=​​RegionPlot​​ImplicitRegion[line,{x,y}],​​PlotRange
h-2r
h+2r
,
k-2r
k+2r
,​​Epilog​​Circle
h
k
,r,​​Red,PointSize@Large,Point
x
y
/.#&/@​​Solveline,
x
y
∈Circle
h
k
,r​​;​​​​​​​​$PreRead=.;(*unset$PreRead*)
crcChord5[{1,2},3,y-x+1==0]
Out[]=