Пример а)
(X+19) * 5 - 16 = 139
(X + 19) * 5 = 139 + 16 = 155
X + 19 = 155 / 5 = 31
X = 31 - 19 = 12
Пример б)
(480 - X) / 6 + 89 = 165
(480 - X) / 6 = 165 -89 = 76
480 - X = 76 * 6 = 456
X = 480 - 456 = 24
