A common misunderstanding of students when they start learning how to work with positive and negative numbers is dealing with the negative of a negative number situation (see below for an example). So along with the rules to add, subtract, multiply and divide positive and negative numbers students also must know how to interpret what the negative of a negative number means. As students get into algebra and beyond they will face the “negative of a negative” situation frequently so it’s critical we eliminate any confusion with this topic.
Rule: the negative of a negative number = a positive number
Ways to think about it…
A negative sign in mathematics actually means “opposite”. So – 2 for example means “the opposite of positive two”. Hence – (– 2 ) means the “opposite of a negative two” . Let’s think about for a second….what is the opposite of a negative two? Well it’s a positive two.
Here are some examples that will help your homeschooler understand this small but important detail in math.
More examples with two numbers..
Hopefully this blog post did its job and ended any confusion over the negative of a negative number. However if you are still having problems with the topic I suggest you take the time during your homeschool week and review Real Number operations– you can use my free videos to get started.