If (A-B-C+D = 12) and (A+B-C-D = 6), what is the value of (B-D)^2?  Choose the correct choice from the following options
A) 4 .	B) 9 .	C) 12 .	D) 16 .	E) 64 .

Rationale: "eq 1 : a - b - c + d = 12 eq 2 : a + b - c - d = 6 ( 1 ) subtract eq 1 from eq 2 a - b - c + d = 12 - a + b - c - d = 6 - - - - - - - - - - - - - - - - - - - - - - - - - 2 b + 2 d = 6 ( 2 ) simplify - b + d = 3 b - d = - 3 ( b - d ) ^ 2 = ( - 3 ) ^ 2 = 9 my answer : b"
Answer: B