Sections:

# Number Line Subtraction

In this section, we will learn how to perform number line subtraction. We will begin by reviewing the operation of subtraction with whole numbers. The subtraction operation is denoted with the "-" symbol. When we think about subtraction with whole numbers, we are basically thinking about taking away from a whole amount or starting value. We will learn how to label the parts of a subtraction problem. The minuend is our starting amount. The minuend is the leftmost number in a horizontal subtraction problem and the top number in a vertical subtraction problem. The subtrahend is the amount being subtracted or taken away from the starting amount. This will be the number after the subtraction symbol in a horizontal subtraction problem or the number below the minuend in a vertical subtraction. Lastly, we come to the answer to the subtraction problem: this is known as the difference. The difference is the amount we have left over after the subtrahend is taken away or subtracted away from the minuend.
Example 1: Identify the parts of 6 - 2 = 4
6 is the minuend or the starting amount
2 is the subtrahend or the amount being taken away
4 is the difference or the amount remaining after 2 is taken away from 6
We will then move into number line subtraction with whole numbers. We previously saw that we could use a number line to visually represent the whole numbers: We can use a number line to give a visual representation of the subtraction operation. This visual understanding will help greatly once we reach the topic of subtracting with integers. When we subtract two whole numbers on a number line, we start out on the number line at the left number of the subtraction problem (minuend). We then move left on the number line by the number of units being subtracted away (subtrahend). The result will be the difference.
Example 2: Subtract 5 - 3 on the number line
Begin at 5, this is our minuend or starting amount
Move 3 units left, 3 is our subtrahend or amount to be taken away
We end up at 2, which is our difference. This is the result of taking 3 away from 5