Question

1 способ.

(45+s)-7 = 218
2 способ.

(45+s)-7 = 218

Answer 1

1 способ.
(45+s)-7 = 218
45+s=218+7
45+s=225
s=225-45
s=180

2 способ.
(45+s)-7 = 218
45+s-7=218
45-7+s=218
38+s=218
s=218-38
s=180

Answer 2

45+s=218+7
45+s=225
s=225-45
s=180