There are two properties involved in the given example:
1) Additive Identity of a number 'x' is a number which, when added to 'x' , yields 'x'.
x + 0 = x
Thus, 8/5 + 0 = 8/5
2) Commutative Property: It states that the result of addition remains same irrespective of the order of numbers.
a + b = b + a
Thus, 8/5 + 0 = 0 + 8/5 = 8/5