7х=14
х=14:7
х=2
20/36х-63/36х+34/36х= -1/4
-9/36х= -1/4
-1/4х= -1/4
х= -1/4:(-1/4)
х= -1/4*(-4)
х=1
4х+12=5х-10
4х-5х= -10-12
-х= -22
х=22
-2х+10+3х-12=4х+1
-2х+3х-4х=1-10+12
-3х=3
х=3:(-3)
х= -1
3х-3=2х+4
3х-2х=4+3
х=7
3х-15-2х-8= -5х+1
3х-2х+5х=1+15+8
6х=24
х=24:6
х=4