To solve this problem, we need to add the two fractions:

$\frac{x}{x+4} + \frac{4}{x+4}$

Since both fractions have the same denominator, $x + 4$, we can add the numerators directly:

$\frac{x + 4}{x + 4}$

Now, we can simplify by canceling out the common factor in the numerator and denominator:

$\frac{x + 4}{x + 4} = 1$

Answer:

The result of the operation in lowest terms is:

$1$

Would you like further explanation, or do you have any additional questions?

Here are 5 additional questions related to this concept:

1. What would happen if the denominators were different?
2. How do you simplify fractions with variables in both the numerator and denominator?
3. Why is it necessary to cancel common factors when simplifying fractions?
4. How do you add or subtract rational expressions with different denominators?
5. What steps would you take to add fractions with polynomials as denominators?

Tip: When adding fractions with the same denominator, you only need to add the numerators and keep the denominator the same.