X/9 - 7/9 = 3 7/9
х/9 = 34/9 + 7/9
х/9 = 41/9
х = 41/9 * 9
х = 41
41/9 - 7/9 = 3 7/9
34/9 = 3 7/9
3 7/9 = 3 7/9
5 4/15 - x/15 = 4 7/15
79/15 - х/15 = 67/15
х/15 = 79/15 - 67/15
х/15 = 12/15
х = 12/15 * 15
х = 12
79/15 - 12/15 = 67/15
67/15 = 67/15
4 7/15 = 4 7/15
3 18/19+ x/19= 15/19
75/19 + х/19 = 15/19
х/19 = 15/19 - 75/19
х/19 = - 60/19
х = - 60/19 * 19
х = - 60
75/19 + (- 60/19) = 15/19
75/19 - 60/19 = 15/19
15/19 = 15/19