Question

Find the vertex of the graph.

f(x) = −x2 + 6x + 1
(x, y) =




Determine whether the graph opens up or down.
The graph opens up.
The graph opens down.

Answer 1

Vertex is (3,10)

open down.

Explanation:

Because the coefficient of x² is negative, the parabola open down.

`f(x)=-x^2+6x+1\\= -(x^2-6x)+1\\=-(x^2-2*3x+3^2-9)+1\\=-(x-3)^2+9+1\\=-(x-3)^2+10\\`

Vertex is (3,10)