Answer:
(0,-1) maximum point
Explanation:
By definition the vertex is the part of the graph where the gradient of the line changes sign (i.e from positive to negative or vice versa). Visually, we can identify this as the point where the graph makes a U-turn.
In this case ,the graph makes a U-turn at (0,-1).
We also notice that the graph is shaped like an "n" as opposed to being shaped like a "u". This means that the U-turn point of the graph represents the largest (i.e the maximum) y-value that that the graph can ever take (i.e there are no y-values on the graph that are above this point).
Hence the vertex (u-turn point) represents a maximum value
hence the answer is (0,-1) maximum point