Warning: call_user_func_array() expects parameter 1 to be a valid callback, function 'app_landing_page_post_entry_header' not found or invalid function name in /var/www/vhosts/ng1-91.pleskbox.com/reshebo.ru/wp-includes/class-wp-hook.php on line 298

Найди и запиши 2 числа, сумма которых равна 9, а произведение — 20.

4 и 5
4 + 5 = 9, 4 * 5 = 20.