Answer:
f(x)=4x(x-3)
Vertex=3/2, -9
Explanation:
First, factorize it.
That is equal to 4x(x-3)
Therefore, x intercepts are 0 and 3, as at least one of them need to be 0.
To find the vertex, first find the x of the vertex, which you can do by finding the average of the x intercepts, so it will be 3/2
Then, find the y, by making x in the original equation equal 3/2. This will give us -9 as the y.
The vertex will by 3/2, -9