For which integers a, b, and c does a – b- c= a- (b – c) Justify your answer.

Answer 1

a – b- c= a- (b – c)
a- b - c = a - b + c
2c = 0
c = 0

any value of a or b, but c has to be zero

e.g. a = 4, b =9 , c = 0

a – b- c= a- (b – c)
4 - 9 - 0 = 4 - (9-0)
-5 = -5 , true!