Subtracting integers using a number line involves visualizing the movement of numbers along the line. Here's a breakdown of the process:
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Start at the first integer (minuend): Locate the first integer in the subtraction problem on the number line. This is your starting point.
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Determine the direction of movement: The subtraction sign indicates movement in the negative direction (to the left). Adding a negative number also means moving to the left. Subtracting a negative number means moving to the right.
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Move the appropriate number of units (subtrahend): Move the number of units indicated by the second integer (subtrahend) in the direction determined in step 2. If you are subtracting a positive number, move to the left. If you are subtracting a negative number, move to the right.
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Identify the ending point: The number on the number line where you end up after moving the appropriate number of units is the answer to the subtraction problem.
Example 1: 5 - 7
- Start at 5 on the number line.
- Since we are subtracting a positive 7, move 7 units to the left.
- You will end up at -2. Therefore, 5 - 7 = -2.
Example 2: 3 - (-2)
- Start at 3 on the number line.
- Since we are subtracting a negative 2, move 2 units to the right.
- You will end up at 5. Therefore, 3 - (-2) = 5.
In summary, use the number line to visualize integer subtraction. Start at the first number and move left for subtracting positive integers, and right for subtracting negative integers. The number you end up on is your answer.
