Math Problem H E L P

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1

Hello People!

So I encountered this problem below. The solution says “Plug In”, which I did but It was a long and confusing process. After like 10 Mins of plugging in I eventually found the answer. My question is: how can i approach this question to answer quick and good other than plugging in? What reflexes should I have?

The Question goes:
If x <y and="" -3x="">y, which of the following must be true?
A) x<0
B) y>0
C) |x|>y
D) x²>y

2

We have x < y and y < -3x, so it is implied by transitivity that x < -3x <==> x is negative. Choice (A) is true.