Answer:
See below.
Step-by-step explanation:
Addition: closed
Example: -5 + 10 = 5, and -5, 10, and 5 are all integers
Subtraction: closed
Example: 10 - 8 = 2, and 10, 8, and 2 are all integers
Multiplication: closed
Example: -4 * 7 = -28, and -4, -7 and -28 are all integers
Division: not closed
Example: 5/2 = 2.5, and 2.5 is not an integer, although 2 and 5 are integers
The set of integers is closed under addition, subtraction, and multiplication because any addition, subtraction, or multiplication of integers always results in an integer.
The set of integers is not closed under division because a division of integers does not always result in an integer.
