Subtracting integers on a number line involves understanding the sign of the number you're subtracting (the subtrahend) and moving in the appropriate direction.
Here's how it works:
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Start at the first number (the minuend) on the number line. This is your starting point.
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Look at the sign of the number you are subtracting (the subtrahend). This determines the direction you'll move.
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If you are subtracting a positive integer: Move to the left on the number line. Each unit you move represents subtracting one.
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If you are subtracting a negative integer: Move to the right on the number line. Subtracting a negative is the same as adding a positive.
Example 1: 5 - 3
- Start at 5 on the number line.
- You are subtracting a positive 3, so move 3 units to the left.
- You end up at 2. Therefore, 5 - 3 = 2.
Example 2: 2 - (-4)
- Start at 2 on the number line.
- You are subtracting a negative 4, so move 4 units to the right.
- You end up at 6. Therefore, 2 - (-4) = 6.
Example 3: -1 - 2
- Start at -1 on the number line.
- You are subtracting a positive 2, so move 2 units to the left.
- You end up at -3. Therefore, -1 - 2 = -3.
In summary: Subtraction on a number line is visualized by moving left when subtracting a positive number and moving right when subtracting a negative number, starting from the initial number.
