Multiplying Integers

Multiplying Integers in NSW Year 8 maths explains why a negative times a negative is positive, then turns it into a quick rule (NESA outcome MA4‑INT‑C‑01): multiply the sizes and count the negative factors. An even count gives a positive answer and an odd count gives a negative one.

You will multiply strings of three or more integers, choose an efficient order, and evaluate powers such as \((-3)^4\) and \(-3^4\), which are not the same. You will find a missing factor or index and spot the pattern in powers of \(-1\). A weekly phone plan charge, a dam level falling each day and salty water cooling in a freezer are all products of integers. It is part of Year 8 Working with Numbers.