GMAT Problem Solving (PS) | Re: If (a-1)(b-2) =0, which of the following must be true ?

if (a-1)(b-2) =0 then one of the following have to be true:

1. a = 1, and b can be any number
2. b = 2, and a can be any number
3. both and a = 1, b = 2

hope this helps

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