Mathematics

Problem

The system

x+y \le 4,\; x \ge 1,\; y \ge 1

has a bounded feasible region. If

x+y \le 4

is replaced by

x+y \ge 4

while keeping

x \ge 1

and

y \ge 1

, state whether the new feasible region is bounded, unbounded or empty, and justify your answer briefly.