To get 8 using the numbers $9, -4, -4, 5, 7$ exactly once, and without parentheses, here is a possible approach:

1. Start by adding $9 + 7 = 16$.
2. Then subtract $16 - 5 = 11$.
3. Now subtract $11 - 4 = 7$.
4. Finally, add $7 + 4 = 8$.

So, the calculation is:
$9 + 7 - 5 - 4 + 4 = 8$

Would you like to explore other ways to achieve the same result, or need further clarification?

Related Questions:

1. How do you solve for a specific number using a set of integers in a given sequence?
2. Can you create a similar equation to obtain 10 using the same numbers?
3. What happens if we only use addition and subtraction with the given numbers?
4. What are alternative methods to solve number puzzles like this one?
5. How can you approach such problems using programming or code?

Tip:

When solving such puzzles, start by combining the largest and smallest numbers and then adjust with the remaining numbers!