Answer:
No, it is a quadratic relation.
Explanation:
Work out the first differences between the given y-values:

As the first differences are not the same, this is not a linear relation.
Work out the second differences:

As the second differences are the same, the relation is quadratic and will contain an x² term. The coefficient of x² is always half of the second difference. As the second difference is 2, the coefficient of x² is one.

Comparing x² with the given y-values, we can see that no further operation is needed. Therefore, the relation is quadratic and the equation is
.