The lengths of the sides of a right triangle are consecutive even integers , and the length of the shortest side is a x . which of the following equations could be used to find x ?

(A) x + x + 1 = x + 2

(B) x^2 + (x + 1)^2 = (x + 2)^2

(C) x^2 + (x + 2)^2 = (x + 4)^2

(D) x + x + 2 = x + 4

(E) x^2 = (x + 2)(x + 4)