First move -2 to the other side
C+(4-3c)=2
Then group the like terms (ones belonging to C)
C(+-) -> C-3c+4=2
The signs change as negative an positive give negative.
Then move the 4 over and apply the motion to the left side of the equation
-2C=7
C= 7/-2 or 3.5
Thats your answer. Hope it helps