Question

Which function has a vertex at the origin?

f(x) = (x + 4)²2
f(x) = x(x-4)
f(x) = (x-4)(x + 4)
f(x) = -x²

Answer 1

f(x) = -x²

Explanation:

Writing f(x) = -x² in vertex form gives f(x)=-(x-0)^2+0 which shows that the vertex (h,k) is at (0,0)

The other equations written in vertex form do not have (h,k) = (0,0)