Question

Suppose that a varies inversely with b^2. If a=9 when b=2, find the value of a when b=3.

Answer 1

a = 4

Explanation:

We can set up an equation to model this:

a =
`(k)/(b^2)`

Now, we can plug in the information given to find the value of k:

9 =
`(k)/(2^2)`

9 =
`(k)/(4)`

36 = k

Now, we can find the value of a when b = 3.

a =
`(36)/(3^2)`

a =
`(36)/(9)`

a = 4