var
  X, Y: LongInt;
begin
  Y := Memo1.Perform(EM_LINEFROMCHAR, Memo1.SelStart, 0);
  X := Memo1.Perform(EM_LINEINDEX, Y, 0);
  inc(Y);
  X := Memo1.SelStart - X + 1;
  Form1.Caption := 'X = ' + IntToStr(X) + ' : ' + 'Y = ' + IntToStr(Y);
end;