The question involves using the Associative Property of Addition to rewrite and evaluate the expression.

Line 1:

$[5 + (-1)] + 9$

Using the Associative Property of Addition, we group the terms differently:

Line 2:

$5 + [(-1) + 9]$

Now let's go step by step to fill in the blanks:

1. Evaluate the expression inside the first set of brackets in Line 1: $5 + (-1) = 4$ So the expression becomes: $4 + 9$ And now: $4 + 9 = 13$ So, the result for the first line is 13.

2. Now for Line 2, evaluate the expression inside the new brackets: $(-1) + 9 = 8$ So the expression becomes: $5 + 8$ And now: $5 + 8 = 13$

Therefore, both lines evaluate to 13.

Final Answer:

• Line 1: $4 + 9 = 13$
• Line 2: $5 + 8 = 13$

Would you like more details or have any questions?

Here are 5 related questions to expand this topic:

1. What is the Associative Property of Addition, and how does it work?
2. Can the Associative Property be applied to subtraction?
3. How does the Commutative Property differ from the Associative Property?
4. How can grouping of terms simplify complex expressions?
5. What are other properties of addition that can be useful in algebra?

Tip: Always check the grouping of terms when using the Associative Property, as the sum remains the same but the order of calculations changes.