Program NN;
Uses crt;
Var a,b: real;
Begin
        Clrscr;
        Write('Nhap a,b: '); Readln(a,b);
        If a=0 then
        Begin
                If b=0 then Write('VO SO NGHIEM')
                Else If b<>0 then Write('VO NGHIEM');
        End
        Else Write(-b/a:0:2);
        Readln
End.

program ctpt;

uses crt;

  var a, b: integer;

begin

           clrscr;

           write('Nhap a = '); readln(a);

           write('Nhap b = '); readln(b);

           if (a=0) and (b=0) then write('Phuong trinh vo so nghiem');

           if (a=0) and (b<>0) then write('Phuong trinh vo nghiem');

           if (a<>0) then write('a khac 0, nhap sai');

           readln

end.