(105 - (25 + 6х) * 4) * 30 = 150
(105 - (100 + 24х)) = 150 : 30
105 - 100 - 24х = 5
24х = 105 - 100 - 5
24х = 0
х = 0 : 24
х = 0
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Проверка: (105 - (25 + 6 * 0) * 4) * 30 = 150
(105 - 25 * 4) * 30 = 150
5 * 30 = 150
150 = 150