Answer
$\begin{cases}x\ge0 \\ x\le20 \\ y\ge15 \\ x-y\le0 \\ x+y\le50 \end{cases}$
Work Step by Step
Based on the given graph, we can identify the equation for the 1st red line as $y-20=(\frac{20-15}{20-15})(x-20)$ or $y=x$,
we can identify the equation for the 2nd red line as
$y-50=(\frac{50-30}{0-20})(x)$ or $x+y=50$,
thus the inequalities
$\begin{cases}x\ge0 \\ x\le20 \\ y\ge15 \\ x-y\le0 \\ x+y\le50 \end{cases}$
