Question

help?!?!?!!

Answer 1

find the vertex first for each

Answer 2

once you find their vertex, you'll see the axis of symmetry

Answer 3

For f(x), its already in vertex form y=a(x-h)^2+k, where the axis of symmetry is x=-h
so its going to be x=-(-8)----> x=8

second one is in standard form y=ax^2+bx+c, to find axis of symmetry which is the x value of the vertex use the formula x=-b/2a

a=3
b=12

x=-12/2(3)
x=?

third one you can easily identify the vertex just by looking at it