You can put this solution on YOUR website! To find the vertex, we first need to find the axis of symmetry (ie the x-coordinate of the vertex)
To find the axis of symmetry, use this formula:
From the equation we can see that a=3 and b=-12
Plug in b=-12 and a=3
Negate -12 to get 12
Multiply 2 and 3 to get 6
Reduce
So the axis of symmetry is
So the x-coordinate of the vertex is . Lets plug this into the equation to find the y-coordinate of the vertex.