Answer
Answers may vary.
$y=-x^2+4$
Work Step by Step
The graph above has a maximum value at $x=0$.
Line of symmetry: $x=-b/2a$
$x=-0/2*-1$
$x=0$
$y=-x^2+4$
$y=-0^2+4$
$y=0+4 = 4$
Line of symmetry is at $x=0$ and goes through $(0,4)$. Since the graph opens down, we know this point is a maximum.
