2(x - 1) = 14
First you can multiply out the brackets:
2(x - 1) = 14
2x - 2 = 14
Now you can add 2 to both sides of the equation:
2x - 2 + 2 = 14 + 2
2x = 16
Now you can divide both sides of the equation by 2 to get 'x' on it's own:
2x/2 = 16/2
x = 8