Answer:
[tex]f(x)=a(x-h)^2+k[/tex]
Vertex form.
Step-by-step explanation:
You are talking about the vertex form for a parabola.
[tex]f(x)=a(x-h)^2+k[/tex] 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.
