What is the common difference of 31, - 169, - 369, - 569?

31 is a positive number, while - 169, - 369, and - 569 is negative.

Step-by-step explanation:

Negative numbers, are numbers less then 0 and include a negative sign that looks like this "-".

Positive numbers are numbers above 0 and don't include a negative sign.

-169, - 369, and - 569 is negative because they have a negative symbol and the number is below 0, while 31 is positive because it's above 0 and doesn't include a negative sign.