How do I find the Direction of Unboundedness for the problem below? I have looked everywhere to see an explanation and have not a found a step by step way to do so.
\begin{alignat}{4} \min \,& z = & \, 50 x_1 & + & 100 x_2 & & & \\ \mbox{s.t.} & & 7 x_1 & + & 2 x_2 & \ge 28 & & \tag{HIW} \\ & & 2 x_1 & + & 12 x_2 & \ge 24 & & \tag{HIM} \\ & & & & \llap{x_1,x_2} & \ge 0 \end{alignat}