Answer
Please see the graph.
Work Step by Step
Green line: $x+y\le1$
$x+y\le1$
$x+y-x \le1-x$
$y \le 1-x$
Since we have the "less than or equal to" sign, we use a solid line. Let's use the point $(0,0)$ to see what side of the line we shade.
$x+y\le1$
$y\le 1-x$
$0 \le 1-0$
$0 \le 1$ (true)
Since this is true, we shade the side of the line that has the point $(0,0)$.
Red line: $y\le-1$
Since we have the "less than or equal to" sign, we use a solid line. Let's use the point $(0,0)$ to see what side of the line we shade.
$y\le -1$
$0\le -1$ (false)
Since this is false, we shade the side of the line that doesn't have the point $(0,0)$.
The union of the two lines is the area that is shaded red or green.