skprocks wrote:With 2, Y can either be -8 or 14. Since, in (1) we know y>2, -8 can't be correct, so it has to be 14, which means both are required to be suff.
In light of what you have explained about stmt1,stmt 2 shall also be always positive.How can it assume both positive and negative values?(-8/14). Sorry to bother you , but the concept behind treating stmt 1 's absolute value as positive and treating the absolute value in stmt2 as either positive or negative is not clear to me.Thanks!!
[/quote]
For statement 2, we are not looking for a solution to the absolute value of 3-y because we already know the answer is positive 11. Rather, for statement 2, we are looking for what Y can be. Y is inside the absolute value, so it can be either positive or negative, and still result in a positive 11.
|3 - y| = 11
Y can either be -8 or 14
|3-14| = |11| = 11
|3- (-8)| = |-11| = 11
So yes, you're correct, the absolute value of 3-y will always be positive, but Y can either be positive or negative.
I got the -8 and 14 by looking at the equation, but if you are unable to simply visualize it, try taking off the absolute value and write 2 equations, one with 11 being positive and one with 11 being negative.
3-Y=11
-Y=11-3
-y=8
y=-8
3-Y=-11
-y=-11-3
-y=-14
y=14
So since statement 2 yields 2 possible answers, we know it's not sufficient.
Now we have 2 answers for what Y can be. In the first statement, Y is NOT the result of an absolute value equation, so it can be either -8 or 14. But, when you plug them in, it will be this:
3|x^2 - 4| = -8-2
3|x^2 - 4| = -10
This is not possible, since a positive 3 times the absolute value of anything will be positive. The equation inside the absolute value doesn't matter, since the result will always be positive. 3 * |anything| = positive
3|x^2 - 4| = 14-2
3|x^2 - 4| = 12
Let me know if you still don't understand. It's hard explaining these things over the computer.
