Given that y varies inversely as x^2, and that y=16 when x=3, what is the value of y when x=4?

Expert Answers
mlsiasebs eNotes educator| Certified Educator

If y is inversely proportional to `x^(2)` then we know that

y (is proportional to) `1/(x^2)`

Since we are given a value for x and y, we can find the value for the numerator so that we are no longer looking at a proportionality but an equation


Now, we can plug in the known values

`16 = z/(3^2)`

`16 = z/9`

z = 16*9

z = 144

Now that we know the value of z, we can use the same equation to solve for the unknown value of y




`y = 9`