6x-2(x+4)=12
First combine the like terms.
6x+x=7x x equals 1x
-2+4=2
Then you need to plug it back in.
7x+2=12
Then you solve for "x".
7x+2=12
subtract 2 on both sides
7x+2=12
-2 -2
The negative and the positive cancel out you are left with 12-2
12-2=10
Now plug that in.
7x=10
Divide 7 on both sides
7x=10
/7 /7
Cancel again left with "x" and 10/7
10/7=1.42
x=1.42