How would you solve different scenarios for this inequality algebraically (not with number substitution):
Is X-Y positive if X+Y is positive?
Fact : X+Y is positivex+y>0
Question: is X-Y positive?x-y>0
You have to try to "lock" one of the terms, your question is too general...
For example if y<0
, we can merge x>-y
And in this case the questionx-y>0
given that x is positive, y is negative is TRUE
It is beyond a doubt that all our knowledge that begins with experience.
Kant , Critique of Pure Reason
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