Question

A coordinate plane shows a parabola that opens downward with a plotted point. Both axes range from negative 8 to 8 in increments of 2.Use the image to answer the question.

A coordinate plane shows a parabola that opens downward with a plotted point. Both axes range from negative 8 to 8 in increments of 2.
▶Click for Long Desc

What is the vertex form of the graphed equation?

(1 point)
y=−2
(x−
)2+
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Answer 1

I can’t see the image you mention. Please either upload it or tell me the coordinates of the vertex and the plotted point on the parabola (or give coordinates of two visible points plus the axis scale).

How to get the answer once you give those numbers:
- The vertex form is y = -2(x − h)^2 + k, where (h,k) is the vertex.
- If you know the vertex (h,k) you’re done: just substitute h and k.
- If you only know another point (x1,y1) and the vertex, plug it in and solve for k:
y1 = -2(x1 − h)^2 + k → k = y1 + 2(x1 − h)^2.

Example: if the vertex is (1,8) and another point is (3,0), then
0 = -2(3−1)^2 + k → 0 = -2·4 + k → k = 8, so y = -2(x−1)^2 + 8.

Tell me the vertex or upload the graph and I’ll give the exact vertex form.