9514 1404 393
Answer:
y = (1/4)x^2 -x -4
Explanation:
When you are given a focus and a vertex, the equation of a parabola can be written as ...
y = (1/(4p))(x -h)² +k . . . . . . vertex (h, k); focus-vertex distance p
Here, the vertex is (h, k) = (2, -5) and the focus-vertex distance is 1. That means the equation of the parabola in vertex form* is ...
y = (1/4)(x -2)² -5
Expanding this equation, we get ...
y = (1/4)(x² -4x +4) -5 = (1/4)x² -x +1 -5
Then the standard form equation is ...
y = (1/4)x² -x -4
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* In the UK, and perhaps other places, the vertex form is referred to as "standard form." You need to be aware of the form that is being requested here. I have answered using the US version of "standard form." YMMV