a) 209 - (145 + x - 12) + 96 = 123209 - 145 - x + 12 + 96 = 123170 - x + 108 = 123-x + 278 = 123-x = -155x = 155
Ответ: x = 155
б) 18 + (159 - y) + 34 = 17218 + 159 - y + 34 = 172211 - y + 34 = 172-y + 245 = 172-y = -73y = 73
Ответ: y = 73
a) 209 - (145 + x - 12) + 96 = 123
209 - 145 - x + 12 + 96 = 123
170 - x + 108 = 123
-x + 278 = 123
-x = -155
x = 155
Ответ: x = 155
б) 18 + (159 - y) + 34 = 172
18 + 159 - y + 34 = 172
211 - y + 34 = 172
-y + 245 = 172
-y = -73
y = 73
Ответ: y = 73