Is |x|=y+1?

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Is |x|=y+1?

by Max@Math Revolution » Wed Aug 24, 2016 4:45 am
Is |x|=y+1?
1) y+x=-1
2) x<0

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by Max@Math Revolution » Thu Aug 25, 2016 5:21 pm
Since there are 2 variables (x and y) in the original condition, there is a high chance that C is the correct answer. Using 1) & 2), we get |x|=-x (when x<0). So from -x=y+1?, x+y=-1?, the answer is yes and the condition is sufficient. Hence, the correct answer is C.

- 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.