Finding the vertex of a quadratic function

7/25/2013

How do you find the vertex of f(x) = (x + 3)² ?

Vertex form of a quadratic function is f(x) = a(x - h)² + k
The vertex has coordinates of (h,k)

In f(x) = (x + 3)²
Since 3 is positive, that means the value of h is -3.
To make +3, it would have to be x - (-3), in vertex form.
The value of k is, of course, 0.

Vertex has coordinates of (-3,0) {as you see in the graph below}