1) х/63 = 52/63 - 29/72
х/63 = 71/168
х = 71/168 * 63
х = 213/8 =26,625
2) 29/42-13/42 - а = 11/42
16/42 - а = 11/42
а = 16/42 - 11/42
а = 5/42
3) 15/17 + 3/17 - b = 6/17
18/17 - b = 6/17
b= 18/17-6/17
b = 12/17
4) 29/43 - 13/43 -m = 5/43
16/43 - m = 5/43
m = 16/43-5/43
m = 11/43