Question

If y varies inversely of the square of x and y= 1/72 when x=3 find y when x =5

Answer 1

`y = (1)/(200)`

Explanation:

`y` ∝
`(k)/(x^(2) )` (k is a constant we need)

`(1)/(72) = (k)/(3^(2) )`

`k = 0.125`

`y = (0.125)/(5^(2) )`

`y=(1)/(200)`