Solved

I used push method and now it’s working as i wanted. Here is last code for those in need.

public function show($id)
    {
        $his = Payment::where('account_id', $id)->with('account')->orderby('id', 'desc')->get();
        $balance = Account::where('id' , $id)->select('balance')->first();
        $history = $his->push($balance);
        return response()->json($history, 200);
    }

Hope it helps.