180:(Х-12)=20 (а+43)*19=797

1. 180 : ( X - 12 ) = 20;
2. 180 : 20 = X - 12;
3. 9 = X - 12;
4. X = 9 + 12;
5. X = 21;
6. Проверка: 180 : ( 21 - 12 ) = 20;
Ответ: X = 21.

1. ( a + 43 ) * 19 = 797;
2. a + 43 = 797 : 19;
3. a + 43 42;
4. a 42 - 43;
5. a -1;
6. Проверка: ( -1 + 43 ) * 19 = 798 797;
Ответ: a = -1.