Subtracting Negative Numbers

You also need to be able to subtract negative numbers comfortably. If you consider negative numbers as debts, then you remove a debt when you subtract a negative number. Removing a debt of 4 dollars is like being given 4 dollars. This explains why the equation 5-(-4)=5+4 holds: subtracting negative four is the same as adding positive four.

The symbols -(-4) also represent the additive inverse OF (the additive inverse of 4). Our work with additive inverses can help you write this expression in a different and simpler way. After all, the additive inverse of 4 is -4, and now the additive inverse of -4 is, by definition, a number that results in zero when added to -4. Of course, the additive inverse of -4 is 4 itself. All of this tells us that -(-4)=4. In the next section we will discuss multiplying and dividing negative numbers.

Watch this video for more examples on how to subtract negative numbers.

Last modified: Tuesday, April 26, 2022, 3:25 PM