1) 2(11х - 5) - 17х = 55
22х - 10 - 17х = 55
22х - 17х = 55 + 10
5х = 65
х = 65 : 5
х = 13
Проверка: 2(11*13 - 5) - 17*13 = 55
2 * 138 - 221 = 55
276 - 221 = 55
55 = 55
2) 5(8х + 3) - 12 = 83
5(8х + 3) = 83 + 12
5(8х + 3) = 95
8х + 3 = 95 : 5
8х + 3 = 19
8х = 19 - 3
8х = 16
х = 16 : 8
х = 2
Проверка: 5(8*2 + 3) - 12 = 83
5 * 19 - 12 = 83
95 - 12 = 83
83 = 83