If xy <> 0, what is the value of 1/x + 1/y?
(1) 1 / (x+y) = -1
(2) xy = 6(x+y)
inequility
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B
1/x + 1/y can be rewritten as (x+y)/xy
Statement 1 : Insufficient
1 / (x+y) = -1
(x+y) = -1
no we can have infinite no of solutions to this, therefore Statement 1 is not sufficient
(1-2)(2-3)(3-4) etc
Statement 2 : Sufficient
xy = 6(x+y)
(x+y)/xy = 1/6
therefore 1/x+ 1/y = 1/6
1/x + 1/y can be rewritten as (x+y)/xy
Statement 1 : Insufficient
1 / (x+y) = -1
(x+y) = -1
no we can have infinite no of solutions to this, therefore Statement 1 is not sufficient
(1-2)(2-3)(3-4) etc
Statement 2 : Sufficient
xy = 6(x+y)
(x+y)/xy = 1/6
therefore 1/x+ 1/y = 1/6