procedure TForm1.Button3Click(Sender: TObject);
Var
  j,x,y,a: integer;
  {y,a: real;}
begin
  a := StrToInt(Edit1.Text);
  with Stringgrid1 do
  begin
    for j := 1 to RowCount do
    begin
      x := StrToInt(cells[1,j]);
      y := sqr(x)*a;
      Cells[0, j] := IntToStr(y);
    end;
  end;
end;

procedure TForm1.Button4Click(Sender: TObject);
var
  i: integer;
begin
  Chart1.Visible := true;
  for i := 1 to StringGrid1.RowCount do
  begin
    Chart1.Series[0].Add(StrToFloat(stringGrid1.Cells[0,i]),'',clred)
  end;
end;