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DS question on finding the value of an unknown.

Question

What is the value of b?
1) a = 3
2) (a-3)(b+2)=0

The OA is E. i.e., Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.

Explanatory Answer
Statement 1: It is obvious that statement 1 is not sufficient. Data given does not provide any information about the value of b. So, we can eliminate choices A and D. So we are down to choices B, C or E.

Statement 2: An equation with two variables 'a' and 'b'. Hence, the information provided is not sufficient.

Note do not make the mistake of solving the equation as either (a - 3) = 0 or (b + 2) = 0 and decide that b = -2. What if only (a - 3) = 0 and (b + 2) was not '0'.

Combining the two statements, we know a = 3, so, (a - 3) = 0. But that leaves the question of what (b + 2) or what 'b' is unanswered.

Hence, choice E is the correct answer.