Given: x + y < 5

Consider: x + y = 5

Now draw a dotted line x + y = 5 in the graph (∵ x + y = 5 is excluded in the given question)

Now Consider x + y < 5

Select a point (0,0)

⇒ 0 + 0 < 5

⇒ 0 < 5 (this is true)

∴ Solution region of the given inequality is below the line x + y = 5. (That is origin is included in the region)

The graph is as follows: