There seems to be a number missing after “3c-“ so we’ll represent the number by x and then try to find out what it could reasonably be.
3(3c-x)=2(c+1),
9c-3x=2c+2,
7c=3x+2.
If x=4:
7c=14 and c=2.
So if the equation had been:
3(3c-4)=2(c+1), then c=2.