Скачать или смотреть Multiplying Integers 1 (7th grade math/prealgebra)

How does multiplying with negative numbers work? You can think of a positive times negative as so many groups of negatives. For example, 5 x (-2) is five groups of two negatives, for a total of 10 negatives. A positive times a negative is negative.

So also is negative times a positive (multiplication is commutative... this also is like so many groups of negatives). But what about a negative times a negative? This topic has baffled mathematicians in the past, so don't worry if it confuses you, too.

We look at a simple pattern to help justify the rule that a negative times a negative is a positive. (There are other ways to justify it also, such as a demonstration that uses the distributive property but it is not covered in the video.)

Math Mammoth Grade 7 curriculum
https://www.mathmammoth.com/complete/...

Integers Bingo Game
https://www.mathmammoth.com/practice/...