Answer:
1) a = 3 , b = -6
2) x-coordinate of the vertex is 1.
3) y-coordinate of the vertex is 10
Step-by-step explanation:
Given function 
1) Identify the values of a and b
The standard form of quadratic function is represented by 
So on comparing with given quadratic function 
We have a = 3 and b = - 6
2) the x-coordinate of the vertex
Given function 
Writing in standard form is
, where (h,k) is the vertex,
We first solve the given function
by using completing square method, we have,
Taking 3 common , we get

Using algebraic identity, 
Here, a = 1 -2ab = -2 so b = 1
So add and subtract 1 both side, we get,

Simplify we get,

Solving , we get,


Thus, (h,k) = (1,10)
And thus x-coordinate of the vertex is 1.
and y-coordinate of the vertex is 10