Wht equation describes a parabola that opens up or down and whos vertex is at the point (h, v)

Vertex form.

Step-by-step explanation:

You are talking about the vertex form for a parabola.

tells us:

A) The vertex is (h,k).

B) Open up (if a is positive) or open down (if a is negative)

C) a also tells us how much it is vertically stretched or compressed.