=(-8)+8+(-5) (additive commutative law)
=(-8)+8+(-5) (additive associative law)
=0+(-5) (0 plus negative number equals negative number)
=-5 (.When a number is added to 0, it still gets this number)
When a=-2, b =-7 and c = 12, a+b a+b+c = 3;; a+(-b)+c= 17。
. . . I thought the same thing.