Question

х:8=37-21
54-х=72:8
39:х=60:20

Answer 1

х:8=37-21
х:8=16
х=16*8
х=128
проверка
128:8=37-21
16=16

54-х=72:8
54-х=9
х=54-9
х=45
проверка
54-45=72:8
9=9

39:х=60:20
39:х=3
х=39:3
х=13
проверка
39:13=60:20
3=3