12 - у = 2у + 6
3х+3=27-5х
-3у-8=2у+7
2х=18-х
7х+3=30-2х
7-2х=3х-18
4х=24+х
8х-8=20-6х
9-4 х = 3х -40
6х=28-х
9х-26=30-5х
7-3 х = 6х -56
11х= 36-х
9х+4=48-2х
8-4х = 2х -16​