(2х+58):42=86
(2х+58)=86*42
2х+58=3612
2х=3612-58
2х=3554
х=3554:2
х=1777
(27х+11)*315=11970
(27х+11)=11970:315
27х+11=38
27х=38-11
27х=27
х=1
6528:(3a-39)=64
(3a-39)=6528:64
3a-39=102
3a=102+39
3a=141
a=141:3
a=47
3х+5х+96=568
8х=568-96
8х=472
х=472:8
х=59