To solve the equation:

$-4 = c - 4$

we can isolate $c$ by following these steps:

1. Add 4 to both sides of the equation to eliminate the $-4$ on the right: $-4 + 4 = c - 4 + 4$

2. Simplify both sides: $0 = c$

So, the solution is: $c = 0$

Would you like further details, or do you have any questions about this solution?

Here are five related questions to expand on this concept:

1. How would you solve a similar equation if it involved multiplication instead, such as $-4 = 2c - 4$?
2. What are the general steps to isolate a variable in an equation?
3. How can we verify the solution to an equation after solving it?
4. What happens if there is no solution to a given linear equation?
5. How would you handle an equation with fractions, such as $-4 = \frac{c}{2} - 4$?

Tip: When solving linear equations, always aim to isolate the variable by performing inverse operations (like adding to cancel subtraction or dividing to cancel multiplication).