14 + (273 - 7x) . 2 = 518
(273 - 7x) . 2 = 504
273 - 7x = 252
7x = 21
x = 3
Vậy...........
(4x + 2)2 - 1 = 35
(4x + 2)2 = 36
(4x + 2)2 = 62
=> TH1: 4x + 2 = 6
4x = 4
x = 1
TH2: 4x + 2 = -6
4x = -4
x = -1
Vậy.....
(358 - x) : 5 = 2 . 52
(358 - x) : 5 = 2 . 25
(358 - x) : 5 = 50
358 - x = 250
x = 108