
Y is the total price. X is the number of months. 30 is a flat, one time payment.
6 cups of cheese servings times 5 = 30
10 cups of cheese servings time 5 = 50
So , it's 10 cups of cheese servings.
I'm assuming this is multiple choice and you forgot to post the answers. I'll take a guess and say it probably looks something like this:

Because you can't take the square root of a negative number without getting an imaginary result, resulting in the function having a closed domain limit.
Answer: (a)
Step-by-step explanation:
Given

Clearly,
is obtained by shifting
3 units down and multiplying it by a certain factor to amplify it.
Checking the option which is 3 units below and multiplying by a factor
option (a) is meeting both the cirterias.