Oksana14011977 Х/72 - 13/72 = 29/72
х/72 = 29/72 + 13/72
х/72 = 42/72
х=42

(29/42 - а) - 13/42 = 11/42
29/42 - а = 11/42 + 13/42
29/42 - а = 24/42
а=29/42 - 24/42
а = 5/42

Санечка69

Verified answer

1)
х/72 -13/72 = 29/72
х/72 = 29/72 + 13/72
х/72 = 42/72
х = 42*72/72
х = 42

2)
(29/42 - а) - 13/42 = 11/42
29/42 - а = 11/42 + 13/42
29/42 - а = 24/42
а = 29/42 - 24/42
а = 5/42