## anonymous one year ago 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

1. anonymous

@AJ01

2. anonymous

last one?

3. ParthKohli

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 $$k =0$$.

4. perl

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

5. anonymous

thanks

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