7(2x-3)-x=3x-11
14 х - 21 -х = 3х -11
(14х -х) - 21 = 3х -11
13х - 21 = 3х -11
13х - 3х = 21- 11
10 х = 10
х = 10: 10
х = 1
проверка
7(2*1 -3) - 1 = 3* 1 -11
- 8 = - 8
7(2x-3)-x=3x-11
14 х - 21 -х = 3х -11
(14х -х) - 21 = 3х -11
13х - 21 = 3х -11
13х - 3х = 21- 11
10 х = 10
х = 10: 10
х = 1
проверка
7(2*1 -3) - 1 = 3* 1 -11
- 8 = - 8