The square root of 9 is 3
the answer to your question is A.
This equation can be written as
(v-8)(v+5)/ (v-8)(v-3)
= v+5/v-3
This is a linear function. Let diameter (inches) be x, circumference (inches) be y, observe that the value of y/x is always 3.14. For example, 15.7/5=31.4/10=...=3.14. Therefore, this is not only a function (one to one correspondence from x to y), it's also a linear function that can be represented as y=3.14x.