When we move to the right on a number line, we represent the addition a positive number. Conversely, movement to the left corresponds to adding a negative number.
Now, we can look at the given number line. Let's start by considering the bottom arrow.
Notice that the arrow starts at 0 and ends at - 3. Therefore, the arrow represents - 3. This means that the first addend in our addition expression and the subtrahend in our subtraction expression are equal to - 3.
Addition
Subtraction
Expression
- 3+?
- 3-?
Result
?
?
Next, we can look at the top arrow on the diagram.
Notice that the arrow is 3 unit to the left of - 3. This means that the arrow represents adding 3, or subtracting - 3. Let's complete our expressions!
Addition
Subtraction
Expression
- 3+3
- 3-( - 3)
Result
?
?
Finally, we can evaluate our expressions. Let's start by performing the addition!
- 3+3= 0
The sum of - 3 and 3 is equal to 0. We know that subtract an integer, we add its opposite. This means that the difference of - 3 and - 3 is also equal to 0. We can use this information to complete our table.
