Answer: E

Statement (1) is insufficient. Move the x's to the right side and the b's to the left:
b + b = x + x
2b = 2x
b = x
Unless we know the value of x, we can't find the value of b.

Statement (2) is also insufficient. Move the x to the right side, and the result is b = x. That's the same as (1)! Since both statements are insufficient on their own and identical, the correct choice is (E). There's no way to put them together to answer the question.