а) 138 + x + 57 = 218x = 218 - 138 - 57x = 23
б) 248 - (y + 123) = 24y + 123 = 248 - 24y + 123 = 224y = 224 - 123y = 101
в) (24 - x) + 37 = 4924 - x + 37 = 4924 - x = 49 - 3724 - x = 12-x = 12 - 24-x = -12x = 12
Проверка:x + 3 = 9 - x12 + 3 = 9 - 1215 = -3 (Неверно)
Правильный ответ:x = 12
а) 138 + x + 57 = 218
x = 218 - 138 - 57
x = 23
б) 248 - (y + 123) = 24
y + 123 = 248 - 24
y + 123 = 224
y = 224 - 123
y = 101
в) (24 - x) + 37 = 49
24 - x + 37 = 49
24 - x = 49 - 37
24 - x = 12
-x = 12 - 24
-x = -12
x = 12
Проверка:
x + 3 = 9 - x
12 + 3 = 9 - 12
15 = -3 (Неверно)
Правильный ответ:
x = 12