Pre algebra help

Question

Y is inversely proportional to the square of x. If y=5 when x=3, then what is y when x is 8

Answer 1

y = k

---

x^2

need to find k, when y = 5 and x = 3

5 = k

----

9

k = 45

so

y = 45

----

x^2

when x = 8

y = 45

----

64