Решите пожалуйста!!!
1. 4y + 7 = 5y + 4;
2. 35 - 11m = 3m + 21;
3. 10 - 9y = 70 - 6y;
4. -9x - 56 = 5x;
5. 56 - 9n = -5n;
6. 15 - 8x = 2 - 9x;
7. 10z + 7 = 9z + 5;
8. 17 - 8y = 4y - 7;
9. 10 - 11n = 15 - 12n;
10. -9z + 32 = 7z;
11. 25 - 12m = 45 - 8m;
12. 5y + 15 = 4y + 20.