audio read-through Determining if a Product is Positive or Negative

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.

Practice

Input your answer as: $\quad+\quad$ or $\quad-$