Adding integers on a number line involves starting at the first integer and moving right for positive integers and left for negative integers, based on the second integer's value.
Here's a breakdown of how to add integers on a number line, explained with examples:
Steps for Adding Integers on a Number Line
- Start at the First Number: Locate the first integer in the addition problem on the number line. This will be your starting point.
- Determine the Direction:
- If the second integer is positive, you will move to the right (towards positive infinity).
- If the second integer is negative, you will move to the left (towards negative infinity).
- Move the Appropriate Number of Units: Move the number of units indicated by the second integer in the direction you determined in Step 2.
- The Ending Point is the Sum: The integer where you land after moving the appropriate number of units is the sum of the two integers.
Examples
Here are some examples to illustrate the process:
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Example 1: 5 + (-4)
- Start at 5 on the number line.
- Since -4 is negative, move 4 units to the left.
- You end up at 1. Therefore, 5 + (-4) = 1.
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Example 2: -3 + 6
- Start at -3 on the number line.
- Since 6 is positive, move 6 units to the right.
- You end up at 3. Therefore, -3 + 6 = 3.
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Example 3: -2 + (-3)
- Start at -2 on the number line.
- Since -3 is negative, move 3 units to the left.
- You end up at -5. Therefore, -2 + (-3) = -5.
Summary
To add integers, we always start with the first number and move towards the right (if positive) or left (if negative) by equivalent units of the second number, according to the provided reference. Using a number line provides a visual representation that can make integer addition easier to understand, especially when dealing with negative numbers.
