Graphing Parabolas

Question

Suppose g(x) = −(x + 3)2 − 4. State the coordinates of the vertex, the axis of symmetry and whether the parabola opens up or down.

Answer 1

The vertex form of any quadratic function is

 

g(x) = a(x - h)² + k

 

 

then the vertex is the coordinate (h, k).

 

 

The vertex of this function is (-3, -4).

 

The axis of symmetry is   x = -3

 

Since the coefficient "a" is negative, the parabola opens downward.