1) x = 12
2) x=18/29
Пошаговое объяснение:
1) х/18-5/18=7/18
х/18=5/18 + 7/18
х/18=12/18
x = 12
2) (16/29+х)-13/29=21/29
16/29+х-13/29=21/29
х=21/29 -16/29+13/29
x =18/29
