Question

11. In which direction does the parabola given by the equation below open? What is the

vertex?

y = -3(x + 4)^2 + 6

Answer 1

The parabola opens downward and the vertex is (-4,6).

Explanation:

Vertex form is this: a(x - h)^2 + k

In your case, a = -3 which is negative so the parabola opens downward. Using this algebraic form, the vertex is at (h,k), but you need to make 4 negative since it is been added rather than subtracted. Thus, the vertex is at (-4,6).