( х -29 ) + 18 / 31 = 1 17 / 31
( х -29 ) + 18 / 31 = 1 17 / 31,
х - 29 = 1 17/31 - 18/31,
х - 29 = 30/31,
х = 29 30/31.
Ответ: х = 29 30/31