Respuesta :

Answer:

a-b= -1

Step-by-step explanation:

according to the question,

a is the predecessor of b ,  it means a is before number of b

a  and b are both integers

Let a =9

b= 10  (as a is predecessor i.e -1 of b)

a-b  =9-10  => -1

hence a-b = -1