if a ( a - 4 ) = 5 and b ( b - 4 ) = 5 , where a ≠ b , then a + b =
"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"
subtract(subtract(subtract(subtract(add(add(4, 5), subtract(4, 5)), const_1), const_1), const_1), const_1)