The value of y varies inversely as sqrt(x) and when x=2, y=4. What is x when y=16?
y = k / sqrt(x)
4 = k / (sqrt 2) k, the proprtionality constant = 4 sqrt 2
16 = 4 sqrt 2 / sqrt x
4 sqrt 2 / 16 = sqrt x
16 * 2 / 256 = x
x = 1/8