Question

How do you write the quadratic in vertex form given `y=3x^2+6x-1`?

Answer 1

The vertex form is:

`y-y_v=a(x-x_v)^2`.

So:

`y=3(x^2+2x)-1rArry=3(x^2+2x+1-1)-1rArr`

`y=3(x^2+2x+1)-3-1rArry=3(x+1)^2-4rArr`

`y+4=3(x+1)^2`.