4х - 5 = 2х + 7 3(х - 2) = 2(х + 2) 4х + 6 = 2(2х + 3)
4х - 2х = 7 + 5 3х - 6 = 2х + 4 4х + 6 = 4х + 6
2х = 12 3х - 2х = 4 + 6 тождество
х = 12 : 2 х = 10
х = 6
х - 1 = 7(1 - х) 2(х + 1) = 3(1 - х)
х - 1 = 7 - 7х 2х + 2 = 3 - 3х
х + 7х = 7 + 1 2х + 3х = 3 - 2
8х = 8 5х = 1
х = 8 : 8 х = 1 : 5
х = 1 х = 0,2