Answer with explanation:
We know that the general equation of a parabola in vertex form is given by:
![y=a(x-h)^2+k](https://img.qammunity.org/2020/formulas/mathematics/high-school/7xiq973pej7bis77rj649g420rebwvc4wx.png)
where the vertex of the parabola is at (h,k)
and if a>0 then the parabola is open upward and if a<0 then the parabola is open downward.
a)
![f(x)=-2(x+3)^2-1](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jodvlmpk52ey9zuihtnt1tph2zx6hdwxlh.png)
Since, the leading coefficient is negative.
Hence, the graph of the function is a parabola which is downward open.
The vertex of the function is at (-3,-1)
b)
![f(x)=-2(x+3)^2+1](https://img.qammunity.org/2020/formulas/mathematics/high-school/f133an5bbet8p1qyfuyuhe9locpzlmqly8.png)
Again the leading coefficient is negative.
Hence, graph is open downward.
The vertex of the function is at (-3,1)
c)
![f(x)=2(x+3)^2+1](https://img.qammunity.org/2020/formulas/mathematics/high-school/izhxjuwnpb3oz5urwbdj2p9bjq3z1p51xs.png)
The leading coefficient is positive.
Hence, graph is open upward.
The vertex of the function is at (-3,1)
d)
![f(x)=2(x-3)^2+1](https://img.qammunity.org/2020/formulas/mathematics/high-school/krord40sjmirpwgadrkecqnzanb520lpnq.png)
The leading coefficient is positive.
Hence, graph is open upward.
The vertex of the function is at (3,1)