(85х+765):170=98 ((х+2)*81-3530)*21=714
85х+765=98*170 (х+2)*81-3530=714:21
85х+765=16660 (х+2)*81-3530=34
85х=16660-765 (х+2)*81=34+3530
85х=15895 (х+2)*81=3564
х=15895:85 х+2=3564:81
х=187 х+2=44 х=44-2 х=42
А) х=3,10
б)у= -2 3/4
в)а = -1
г) z = 0
д) b = 100