Question

Find the constant of variation for the relation and use it to write an equation for the statement. Then solve the equation. If y varies inversely as the square of x, and y=7/4 when x=1, find y when x=3

Answer 1

y=7/36

Explanation:

Since y varies inversely to the square of x, we can say

`y = z/x^2`

where z is the constant of variation.

Then, from knowing that y=7/4 when x=1, we plug them in to find z.

`7/4=z/(1^2)\\z=7/4`

Now we have the full equation,

`y=7/4x^2`

Plug x=3 in and we get,

`y=7/4(3^2) = 7/36`