﻿ Determining if a Product is Positive or Negative
DETERMINING IF A PRODUCT IS POSITIVE OR NEGATIVE

by Dr. Carol JVF Burns (website creator)
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• PRACTICE (online exercises and printable worksheets)
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Recall the following properties of multiplication of signed numbers:

(positive)(positive) = positive
(positive)(negative) = negative
(negative)(negative) = positive

When more than two numbers are being multiplied, just count the number of minus signs:
any even number of minus signs collapses to a plus sign;
any odd number of minus signs collapses to a minus sign.

EXAMPLES:
The product $\,(+)(-)(-)(+)(-)\,$ is negative $\,(-)\,$.
In this example, there are $\,3\,$ minus signs; $\,3\,$ is an odd number.
The product $\,(-)(-)(+)(-)(-)\,$ is positive $\,(+)\,$.
In this example, there are $\,4\,$ minus signs; $\,4\,$ is an even number.
Master the ideas from this section
Input your answer as: $\quad+\quad$ or $\quad-$
Determine the sign of this product: $\quad+\quad$ or $\quad-\quad$