Question

A parabola has a vertex at (-1, 0) and opens down.

What is the equation of the parabola?

y = -x^2 - 1
y = -(x - 1)^2
y = -(x + 1)^2

Answer 1

@AJ01

Answer 2

last one?

Answer 3

There's not enough information in the question, because the general vertex-form a parabola is\[f(x) = a(x-h)^2 + k\]where \((h,k)\) is the vertex. All of your choices have \(a=-1\), so might as well assume that.\[f(x) = -1\cdot(x-h)^2 + k\]It is given that \(h = -1\) and \(k =0\).

Answer 4

if you use
f(x) = a(x-h)^2 + k , you are given h = -1, and k = 0. plug that in. also you know that a<0 since the parabola points downwards

Answer 5

thanks