Question

If Y varies inversely as x^2. If y=2 when x=10, how do you find y when x=5?

Answer 1

Hence y varies inversely as x^2 then there is a constant `k` such as

`y=k/x^2`

Hence when `x=10` then `y=2` the constant `k` is

`k=y*x^2=2*10^2=200`

So when x=5 then

`y=k/x^2=200/5^2=200/25=8`