б)4,58х+2,42х=7,14
7х=7,14
х=7,14:7
х=1,02
4,58*1,02+2,42*1,02=7,14
4,6716+2,4684=7,14
7,14=7,14
в)7,14х+17,86х=38
25х=38
х=38:25
х=1,52
7,14*1,52+17,86*1,52=38
10,8528+27,1472=38
38=38
г)199,29х-119,29х=72
80х=72
х=72:80
х=0,9
199,29*0,9-119,29*0,9=72
179,361-107,361=72
72=72