[Страдалецъ]

Можно так:

Код:

program Project32;

{$APPTYPE CONSOLE}

uses
  SysUtils;

Type
 TFirstObject = object
   X,Y: Integer;
   procedure SetXY(NewX,NewY: Integer); virtual;
 end;

 TSecondObject = object(TFirstObject)
   procedure SetXY(NewX,NewY: Integer); virtual;
 end;


procedure TFirstObject.SetXY(NewX,NewY: Integer);
begin
 X := NewX; Y := NewY;
end;

procedure TSecondObject.SetXY(NewX,NewY: Integer);
begin
 TFirstObject.SetXY(NewX,NewY);
 X := X*10; Y := Y*10;
end;

Var
  FirstObject: TFirstObject;
  SecondObject: TSecondObject;
begin
 FirstObject.SetXY(1,1);
 SecondObject.SetXY(1,1);
 WriteLn('FirstObject: ',FirstObject.X:4,FirstObject.Y:4);
 WriteLn('SecondObject: ',SecondObject.X:4,SecondObject.Y:4);
 ReadLn;
end.

TSecondObject = object(TFirstObject)
procedure SetXY(X: Integer); virtual;
end;