Giải HPT

uses crt;
var
  a,b,c,a1,b1,c1:integer;
  x,y,d,d1,d2:real;
begin
  clrscr;
  write('Nhap a,b,c,a1,b2,c3:');
  readln(a,b,c,a1,b1,c1);
  d:=a*b1-b*a1;
  d1:=c*b1-b*c1;
  d2:=a*c1-c*a1;
  if (d=0) and ((d1<>0) or (d2<>0)) then writeln('Phuong trinh vo nghiem');
  if (d=0) and (d1=0) and (d2=0) then writeln('Phuong trinh vo so nghiem');
  if d<>0 then
    begin
      x:=d1/d;
      y:=d2/d;
      writeln('Nghiem cua phuong trinh la: x=',x,', y=',y);
    end;
  readln;
end.