Question

What is the axis of symmetry and vertex for the graph `f(x)= -x^2+4x-1`?

Answer 1

The axis of symmetry is the line `x = 2` and the vertex is `(2.3)`

Explanation:

The formula to find the axis of symmetry is: `x = (-b)/(2a)`
`x = (-4)/(2(-1)) = 2`

The vertex is on the axis of symmetry.
Substitute `x = 2` into the equation to find the `y-value`
`y = -(2)^2 + 4(2) - 1` which gives `y = 3`

Vertex is (2,3)