Опрос от журнала "8 часов": "Чем Вы питаетесь на работе?"

Doesn't Add Up
a is the sum of x consecutive positive integers. b is the sum of y consecutive
positive integers. For which of the following values of x and y is it
impossible that a = b?

(A) x = 2; y = 6
(B) x = 3; y = 6
(C) x = 7; y = 9
(D) x = 10; y = 4
(E) x = 10; y = 7