Answer:
to square a number you multiply the number by itself.
a positive number times a positive number is a positive number.
a negative number times a negative number is a negative number.
and if you are multiplying 2 numbers with the same sign they will always be a positive number.
You have the following function:

Derivate implictly the previous expression, as follow:

Where you have used that:

Then, the implicit derivative of the given expression is:

Next, solve for y' as follow:

You didn’t provide a picture
Answer:
t+4, t≠8
Step-by-step explanation:

The value of t must not be one that makes the denominator zero, hence must not be 8.