We have this system of inequalities
which is equivalent to this system
where z = 2x+3y
What number is larger than 9 AND smaller than -6 at the same time?
No such number exists.
There are no solutions.
In reference to tutor josgarithmetic's graph, 3y>9-2x aka 2x+3y > 9 has you shade above the line 2x+3y = 9 (the red line in their graph).
while 2x+3y < -6 means you shade below the parallel green line 2x+3y = -6
These shaded regions do not overlap, which is a visual indicator of "no solutions"