Помогите с уравнением!!4 x - 9=2x

4 x - 9=2x +11        6x+9=2x+33                5x+6=7x-10                   11x-50=x
4х - 2х=9+11          6х - 2х= - 9+33            6+10= - 5х +7х              11х -х=50
2х=20                     4х=24                          16=2х                            10х=50
х=20 : 2                  х=24 : 4                        х=16 : 2                         х=50 : 10
х=10                       х=6                               х=8                                х=5

2x=9x-21
21=9х - 2х
21=7х
х=21 : 7
х=3

1)х+2=3х-4
х-3х=-4-2
-2х=-6
х=3
2)4х-9=2х-11
4х-2х=-11+9
2х=-3
х=-1,5
3)6х+9=2х+33
6х-2х=33-9
4х=24
х=6
4)5х+6=7х-10
5х-7х=-10-6
-2х=-16
х=8
5)11х-50=х
11х-х=50
10х=50
х=5
6)2х=9х-21
2х-9х=-21
-7х=-21
х=3