A) (x + 15) - 8 = 17x + 15 - 8 = 17x + 7 = 17x = 17 - 7x = 10
Проверка:(10 + 15) - 8 = 1725 - 8 = 1717 = 17 (верно)
Б) (45 - y) + 18 = 5845 - y + 18 = 58-y + 63 = 58-y = 58 - 63-y = -5y = 5
Проверка:(45 - 5) + 18 = 5840 + 18 = 5858 = 58 (верно)
В) 56 - (x + 12) = 2456 - x - 12 = 2444 - x = 24-x = 24 - 44-x = -20x = 20
Проверка:56 - (20 + 12) = 2456 - 32 = 2424 = 24 (верно)
A) (x + 15) - 8 = 17
x + 15 - 8 = 17
x + 7 = 17
x = 17 - 7
x = 10
Проверка:
(10 + 15) - 8 = 17
25 - 8 = 17
17 = 17 (верно)
Б) (45 - y) + 18 = 58
45 - y + 18 = 58
-y + 63 = 58
-y = 58 - 63
-y = -5
y = 5
Проверка:
(45 - 5) + 18 = 58
40 + 18 = 58
58 = 58 (верно)
В) 56 - (x + 12) = 24
56 - x - 12 = 24
44 - x = 24
-x = 24 - 44
-x = -20
x = 20
Проверка:
56 - (20 + 12) = 24
56 - 32 = 24
24 = 24 (верно)