(х - 3 12/17) - 8 9/17 = 4 10/17
х - 3 12/17 = 4 10/17 + 8 9/17 = 12 19/17 = 13 2/17
х = 13 2/17 + 3 12/17 = 16 14/17
х = 16 целых 14/17
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Проверка: (16 14/17 - 3 12/17) - 8 9/17 = 4 10/17
13 2/17 - 8 9/17 = 4 10/17
12 19/17 - 8 9/17 = 4 10/17
4 10/17 = 4 10/17