So,
Given the function:

To check if the function is continuous in the entire number real line, we need to analyze the restrictions in the domain.
As you can notice, the denominator of a rational function can't be zero, so:

We're going to find the values of x such that:

This is:

As you can see, "x" can't take the values of 6 and -6. If that happens, the function is not defined. Thus, the function is not continuous on the entire real number line.