Can anyone please explain this again? It’s not intuitively coming to me how we can subtract the inequalities. I converted −y<4 to y>-4. And then tried subtracting but that’s wrong, right?
Hey @devanshijain024 ,
I think the approach is more logical than conceptual. Also you might have misunderstood the equalities. check timestamp 00:32
From the given inequalities we can a few things
- x is always greater than 9. x can go as low at 9 (not exactly 9)
- y < 4, meaning y can go as high as 4 (not exactly 4)
Knowing this, we can say for sure that when x is subtracted from y we get a certain value.
Let’s take x = 9, because minimum value and y = 4 because maximum value and do x - y. This gives us 5 hence we can say for sure that x - y > 5 because x can be greater than 9 or y less than 4 or both in which case the answer will only increase.
Hope this helps!
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