Year 8 Interactive Maths - Second Edition

Multiplication of Integers

The Product of Two Positive Integers

Consider the product 3 × 4.

This suggests that:

The product of two positive integers is a positive integer.

Example 10

Find the value of:

Solution:

The Product of Two Negative Integers

Consider the product –3 × – 4.

This suggests that:

The product of two negative integers is a positive integer.

Example 11

Find the value of:

Solution:

The Product of a Positive Integer and a Negative Integer

Consider the product 4 × –3.

This suggests that:

The product of a positive integer and a negative integer is a negative integer.

Example 12

Find the value of:

Solution:

Just to recap the foregoing discussion:

• The product of two numbers with like (i.e. the same) signs is always positive.
• The product of two numbers with unlike (i.e. different) signs is always negative.