Question

Suppose that y varies inversely as the square of x, and that y = 9 when x = 19. What is y when x = 17? (Round off your answer to 2 decimal places.)

Answer 1

y = k/x^2

That is, x^2y = k is constant.
So, you want y such that

19^2 * 9 = 17^2 * y