Evaluate this limit, if it exists:

lim (7-x)squared - 9 / 4-x
x->4

To evaluate the given limit, we substitute 4 into the expression and simplify.

First, let's substitute x = 4 into the expression (7 - x)^2 - 9 / (4 - x):

lim (7 - x)^2 - 9 / (4 - x) = (7 - 4)^2 - 9 / (4 - 4)
= 3^2 - 9 / 0

At this point, we have an indeterminate form of a fraction with a zero denominator. This means that the limit may not exist, but we need to do further analysis to be sure.

Let's simplify the expression further:

3^2 - 9 / 0 = 9 - 9 / 0

Now, we can see that we have a division by zero, which is undefined. Therefore, the limit does not exist in this case.

In summary, the limit of the given expression as x approaches 4 does not exist because we encountered a division by zero situation.