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thp510
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Is x·|y| > y2?
(1) x > y
(2) y > 0
OA: C
Here's how I tried to rephrase.
Step 1a) First, I lets say Y is positive. So the inequality becomes:
x(y) > (+y)(+y)
Step 1b) Divide out the positive y on both sides and you get
x>y
Now, what if y was negative. Here's how I took the inequality.
x(y) > (-y)(-y)
Step 2a) Divide out the negative y and switch the inequality sign
(x*y)/(-y) > (-y*-y)/(-y)
-x<-y
Step 2b) Now, I divided by -1 again (I hate working with neg variables). When doing so, I switched the inequality once more.
x>y
So no matter what, the DS question is asking, "Is X>Y" ? So what's wrong with my approach other than the obvious numbers I can plug in to prove this is wrong? I initially choose A after doing both scenarios.
[/spoiler]
(1) x > y
(2) y > 0
OA: C
Here's how I tried to rephrase.
Step 1a) First, I lets say Y is positive. So the inequality becomes:
x(y) > (+y)(+y)
Step 1b) Divide out the positive y on both sides and you get
x>y
Now, what if y was negative. Here's how I took the inequality.
x(y) > (-y)(-y)
Step 2a) Divide out the negative y and switch the inequality sign
(x*y)/(-y) > (-y*-y)/(-y)
-x<-y
Step 2b) Now, I divided by -1 again (I hate working with neg variables). When doing so, I switched the inequality once more.
x>y
So no matter what, the DS question is asking, "Is X>Y" ? So what's wrong with my approach other than the obvious numbers I can plug in to prove this is wrong? I initially choose A after doing both scenarios.
[/spoiler]












