The function f(x) is shown on the graph.
If f(x) = 0, what is x?
18fy
15-
O O only
O 6 only
O-2, 1, or 3 only
0 -6, -2, 1, or 3 only
12-
fixy
9-
6
3-
-3
+
-1
X
-3-
-6
712
-15+
-187