Question

If a is a positive integer and b is a negative integer, which expression must be positive?

A. a-b
B. a+b
C. a•b
D. a/b

Answer 1

So, let's solve all of them and see:

a - (-b) = a + b ⇒ can be either positive or negative, depending on the numbers

a + (-b) = a - b ⇒ can either be positive or negative, depending on the numbers

a * (-b) = a * (-b) ⇒ negative answer no matter what

a / (-b) = a / (-b) ⇒ negative answer no matter what

So the answer is:

"None of the above".

Hope it helped,

BioTeacher101

(If you have any questions, feel free to ask them in the comments)

Answer 2

If  A is a positive integer and  B is a negative integer,  The expression that is positive:  =====>   Answer NONE OF THEM

A. a   -   b    =====>  

B. a  +  b  =====>    Zero (0)

C. a  •   b

D. a  /  b =====>   A and B can take any values, Either Negative or Positive

Answer would be, NONE OF THE ABOVE

Hope that helps:            : )