Answer:
Given inequality,

For graphing the inequality :
The related equation of the given inequality,
x + y = 1
Having the x-intercept = (1,0),
y-intercept = (0,1),
Also, at (0,0),
0 + 0 < 1 ( True )
⇒ The area of the given inequality x + y < 1 must contain the origin.
Now, '<' show the dotted line.
Thus, by the above explanation we can plot the graph of the given inequality.