Question

How do you find the axis of symmetry, graph and find the maximum or minimum value of the function `f(x) = x^2 + 6x - 7`?

Answer 1

Vertex `(-3,-16)`

Axis of symmetry `x=-3`

Explanation:

Given -

`y=x^2+6x-7`

Vertex

`x=(-b)/(2a)=(-6)/(2xx1)=-3`

At `x=-3`

`y=(-3)^2+6(-3)-7`
`y=9-18-7=-16`

Vertex `(-3,-16)`

Axis of symmetry `x=-3`

Since the coefficient of `x^2` is positive, the parabola opens up.

Take a few points on either side of `x=-3`. Find the corresponding `y` values . plot them on a graph sheet. join all the points with the help of a smooth curve. You get the parabola.