To solve this, you need to isolate/get the variable "c" by itself in the equation:
4c + 8c = -55 + 3c You can first combine like terms (4c and 8c)
12c = -55 + 3c Subtract 3c on both sides
9c = -55 Divide 9 on both sides
[tex]c=-\frac{55}{9}[/tex]