Respuesta :

The answer is 7 and 2.
First we find the factors of 28 that are:
 factors of 28 = 1,2,4,7,14,28
now 7 and 2 are the factors of 28 and if we add them we get the answer 9
7 + 2 = 9 
So, 7 and 2 are the two factors of 28 that add up to 9.