Prove solution does not exist for inequalities system

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I have an inequalities sytem like the following:

Example

> x+y+z <= A
> x+y <= B
> x+z > C
> y+z > D
> x >= E

Let A,B,C,D,E be any constant value.

Notice that the coeficient of the variables are always 1. So an equation matrix will always look like this:

(1   1   1 | <= A)
(1   1   0 | <= B)
(1   0   1 | <  C)
(0   1   1 | >  D)
(1   0   0 | >= E)

Each row represents a plane in 3D space.

The solution to this sytem has a geometrical 3D representation which is a volumne space. So if the volume is greater than 0, there is a solution!

Is there a way to tell if all this equations have at least one feasible solution? or in other words, is there a "volume" contoured by this planes??