As given by the question
(1)
There are given that the equation:

Now,
Put the value of y is 27 and x is 3 into the above equation to check the solution
So,
From the equation:

Hence, the answer is No.
Now,
(2):
From the equation:

Now,
The graph of the given equation is shown below:
According to the question,
There are given that negative values, that means -3.
So, the graph of the parabola is downwards from the origin.