3х-(10-9х)=22х 21х+45=15+14х 13х+40=2х+7 25-(7-2х)=5х

1)3х-(10-9х)=22х
3х-10+9х=22х
3х+9х-22х=10
-10=10х
Х=-1

2)21х+45=15+14х
21х-14х=15-45
7х=-30
Х=(-30)/7

3)13х+40=2х+7
13х-2х=7-40
11х=-33
Х=-3

4)25-(7-2х)=5х
25-7+2х=5х
25-7=5х-2х
18=3х
Х=6