Răspuns :
3² - x = 1 / 9
9 - x = 1 / 9
(81 - 9x) : 9 = 1 / 9
81 - 9x = 1
9x = 80, x = 80 / 9.
9 - x = 1 / 9
(81 - 9x) : 9 = 1 / 9
81 - 9x = 1
9x = 80, x = 80 / 9.