Question

How do you write `y = 4x^2 -8x +9` in vertex form?

Answer 1

See below.

Explanation:

Vertex forms is:

`y=a(x-h)^2+k`

We want to make the equation like this.

`y = 4x^2 -8x +9=y = 4(x^2 -2x) +9`
`=4(x^2 -2x+1)-4 +9` (when you add one inside the parenthesis, you subtract `4` on the outside, as `a` is `4`).

`=4(x-1)^2+5`