Originally Posted by

**Jhevon** finding the roots is one way (which we can do by factoring or the quadratic formula or completing the square ...) but it's easier to just find the vertex directly. we can do this through completing the square or by using the vertex formula.

Vertex formula:

The vertex for a quadratic of the form $\displaystyle y = ax^2 + bx + c$ occurs when:

$\displaystyle x = \frac {-b}{2a}$

Completing the square:

we complete the square to get the quadratic in the form: $\displaystyle y = a(x - h)^2 + k$

when in this form, the vertex is given by: $\displaystyle (h,k)$

here, the x-value is your Q