Is a=b?

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Is a=b?

by Max@Math Revolution » Sun Jul 10, 2016 11:50 pm
Is a=b?
1) a^2=b^2
2) a=1

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by Max@Math Revolution » Mon Jul 11, 2016 5:25 pm
There are 2 variables in the original condition. In order to match the number of variables and the number of equations, we need 2 equations. There is a high chance that C is the correct answer. Using 1) & 2), from a=1 and b=-1, 1, the answer is both yes or no. Hence, the conditions are not sufficient and the correct answer is E.

- Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.