(223440 - 130х) : 35 = 6020
223440 - 130х = 6020 * 35
223440 - 130х = 210700
130х = 223440 - 210700
130х = 12740
х = 98
-------------------------------------
(31 * 550 - х) * 120 = 10200
(17050 - х) = 10200 : 120
17050 - х = 85
х = 17050 - 85
х = 16965