Question

What is the vertex form of `y=(x – 8)(x + 5)`?

Answer 1

Vertex form is `y = (x - 3/2)^2 - 169/4`

Explanation:

Start by multiplying out.

`y = x^2 - 3x - 40`

Now complete the square.

`y = 1(x^2 - 3x + 9/4 - 9/4) - 40`

`y = 1(x^2 - 3x + 9/4) - 9/4 - 40`

`y = 1(x - 3/2)^2 - 169/4`

Hopefully this helps!