решить уравнение 2(х-8)=20;2х-(7+х)=2;6+12:y=16.

2х-16=20

2х=20+16

2х=36

х=18

2х-7-х=2

х-7=2

х=2+7

х=9

6+12/у=16

12/у=16-6

12/у=10

у=12/10

у=6/5=1,2

2(х - 8) = 20                2х - (7 + х) = 2          6 + 12 : у = 16

2х - 16 = 20                 2х - 7 - х = 2             12 : у = 16 - 6

2х = 20 + 16                х = 2 + 7                    12 : у = 10

2х = 36                        х = 9                           у = 12 : 10

х = 36 : 2                                                        у = 1,2

х = 18