1) - 7 + х = 13 2) х + (- 9) = - 4
х = 13 + 7 х = - 4 + 9
х = 20 х = 5
- 7 + 20 = 13 5 + (- 9) = - 4
13 = 13 - 4 = - 4
3) х + (- 15) = 10 4) 8 + х = - 12
х = 10 + 15 х = - 12 - 8
х = 25 х = - 20
25 + (- 15) = 10 8 + (- 20) = - 12
25 - 15 = 10 8 - 20 = - 12
10 = 10 - 12 = - 12
5) - 6 + х = 5 6) х + (- 14) = - 8
х = 5 + 6 х = - 8 + 14
х = 11 х = 6
- 6 + 11 = 5 6 + (- 14) = - 8
5 = 5 6 - 14 = - 8
- 8 = - 8
1) - 7 + х = 13 2) х + (- 9) = - 4
х = 13 + 7 х = - 4 + 9
х = 20 х = 5
- 7 + 20 = 13 5 + (- 9) = - 4
13 = 13 - 4 = - 4
3) х + (- 15) = 10 4) 8 + х = - 12
х = 10 + 15 х = - 12 - 8
х = 25 х = - 20
25 + (- 15) = 10 8 + (- 20) = - 12
25 - 15 = 10 8 - 20 = - 12
10 = 10 - 12 = - 12
5) - 6 + х = 5 6) х + (- 14) = - 8
х = 5 + 6 х = - 8 + 14
х = 11 х = 6
- 6 + 11 = 5 6 + (- 14) = - 8
5 = 5 6 - 14 = - 8
- 8 = - 8