1. **State the problem:** Simplify the expression $4x - 2c + 4x$. 2. **Identify like terms:** Terms with $x$ are like terms and can be combined. The term with $c$ is different and stays as is. 3. **Combine like terms:** $$4x + 4x = 8x$$ 4. **Write the simplified expression:** $$8x - 2c$$ 5. **Explanation:** We added the coefficients of $x$ terms because they represent the same variable, while the $-2c$ term remains unchanged as it is a different variable. **Final answer:** $8x - 2c$