1) 57,3-11*х=18,14
39.16-11*x=0
x=39.16/11
x=3.56
2) 17,6:х-2,27=1,73
17.6:x-4=0x=17.6:4
x=4.4
3) 4,36-5,28:х=1,36
3-5.28:x=0x=-5.28:(-3)
x=1.76
4) (х+2,67) : 7=0,86
x/7=67/140x=67/140*7
x=3.35
21*6=126S1=126(м)
21*6=126S2=126(м)
9*12=108
S3=108(м)
30*12=360Sобщая=360