If a(a - 4) = 5 and b(b -4) = 5, where a ≠ b, then a + b =  Pick one.
A) − 48	B) − 4	C) 4	D) 9	E) 48

Rationale: "i . e . if a = - 1 then b = 5 or if a = 5 then b = - 1 but in each case a + b = - 1 + 5 = 4 answer : option c"
Answer: C