Using Number Lines to Subtract Integers

A step-by-step guide to using Number Lines to Subtract Integers

To subtract integers using a number line, you have to move in the opposite direction from adding integers.
Utilize a number line to add and subtract integers:

• To add positive integers, move towards the right on a number line.
• To add negative integers, move towards the left on a number line.
• To subtract integers, add their opposites.

Here’s how to subtract integers using a number line:

1. Start at the first number (the minuend) and move to the left for each unit of the second number (the subtrahend). For example, if you’re subtracting -3 from 4, start at 4 and move 3 units to the left.
2. Label the endpoint of the distance you traveled with the difference. So in the example above, the difference would be labeled as 1.
3. Write the difference as the solution to the subtraction problem. In this case, the solution would be 4 – (-3) = 1.

Note: When subtracting a positive number, you move to the left on the number line. When subtracting a negative number, you move to the right on the number line.

Using Number Lines to Subtract Integers – Example 1

Solve \((-8)-(-14)=\)? and graph on the number line.
Solution:
Step 1: Find the first number on the number line. \(-8\)
Step 2: Change the second number’s sign to its opposite. (Convert subtraction into addition). \(-14→14\)

Using Number Lines to Subtract Integers – Example 2

Solve \(7-11=\) ? and graph on the number line.
Solution:
Step 1: Find the first number on the number line. 7
Step 2: Change the second number’s sign to its opposite. (Convert addition into subtraction). \(11→-11\)