Given equation is x - y <= 0 ..........1

Now we draw the graph for x - y = 0 ..........2

1. Put x = 0, y = 0 in eqation 1, we get

0 - 0 <= 0

=> 0 <= 0 which is true.

2. Put x = 1, y = 1 in eqation 1, we get

1 - 1 <= 0

=> 0 <= 0 which is true.

2. Put x = -1, y = -1 in eqation 1, we get

-1 - (-1) <= 0

=> -1 + 1 <= 0

=> 0 <= 0 which is true.

Now it forms a straight line passing through the origin.