Here equation of line $\mathrm{OC}$ is $\mathrm{y}=\mathrm{x}$ i.e. $\mathrm{x}-\mathrm{y}=0$ and equation of line $\mathrm{AB}$ is $\mathrm{x}=5$ i.e. $\mathrm{x}-5=0$
Equation of line $\mathrm{BC}$ is $\mathrm{y}=3$ i.e. $\mathrm{y}-3=0$
Hence constraints for the shaded region are $x, y \geq 0, x-5 \leq 0, x$
$\begin{aligned}
& -y \geq 0, y-\leq 0 \\
& \text { i.e. } x, y \geq 0, x \leq 5, x-y \geq 0, y \leq 3
\end{aligned}$