1. The problem is to make $c$ the subject of the formula from $f = 5c - 8$. 2. Start with the equation: $$f = 5c - 8$$ 3. Add 8 to both sides to isolate the term with $c$: $$f + 8 = 5c - 8 + 8$$ $$f + 8 = 5c$$ 4. Divide both sides by 5 to solve for $c$: $$\frac{f + 8}{5} = \frac{5c}{5}$$ $$c = \frac{f + 8}{5}$$ 5. Therefore, the subject $c$ is: $$c = \frac{f + 8}{5}$$