Where can you find the solutions to the cell phone situation in the graph?

In the overlap of green and orange regions, however note that because the cell phones are indivisible physical objects, only the lattice points are possible solutions.

The solution of a system of linear inequalities contains the set of all points which make the given inequalities true. Points in the solution set are located in the shaded regions where the inequalities overlap.

Depending on the situation, the number of solutions to a system of inequalities, can be none, infinite or anything in between.