Each week Manhattan GMAT posts a GMAT question on our blog and follows up with the answer the next day. Are you up for the challenge?
If the quantity 52 + 54 + 56 is written as (a + b)(a – b), in which both a and b are integers, which of the following could be the value of b?
(A) 5
(B) 10
(C) 15
(D) 20
(E) 25