When the positive integer is greater than the negative integer.
any positive integer
It is an integer.
The sum of a positive integer and a negative integer is positive when the positive integer is greater. For example: 9 + (-5) = 4 In this case, the positive integer 9 is greater than the negative integer 5. Therefore, the sum is positive.
a positive integer
By definition, a negative integer is any integer less than zero. Similarly, a positive integer is any integer greater than zero. It should be immediately obvious that an integer cannot be both less than and greater than zero. Therefore, a negative integer cannot be greater than a positive integer.