решите уравнение: 5/9 + (х- 2/9 ) = 7/9
5/9 + (х- 2/9 ) = 7/9
3/9+х=7/9
х=4/9
5/9+х-2/9=7/9
х+3/9=7/9
х+1/3=7/9
х=7/9-1/3