Problem Solving (PS) | Re: In the x- y plane, there are 4 points (0,0), (0,4), (6,4), and (6,0).

Bunuel Could you please explain why do we take (0,4) and (4,0) to form a triangle and not (0,3) and (3,0) ?
We want x+y to be <4.
At the point (0,4) , x=0 and y=4 , hence x+y are not <4. What am I missing here?

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