Isolate the x. Note the equal sign. What you do to one side, you do to the other.
Add 1 to both sides, and add 3x to both sides
3x (+3x) - 1 (+1) = 1 (+1) - 3x (+3x)
3x + 3x = 1 + 1
Simplify
6x = 2
Isolate the x. Divide 6 from both sides
6x/6 = 2/6
x = 2/6
x = 1/3
1/3 is your answer for x.
hope this helps