Question 57200
If y varies inversely as X^2 and y= -8 when x=2, find  y if x=3. 
First we need to find the constant of variation.
y varies inversely as {{{x^2}}} is:
{{{y=k/x^2}}}
We can find the constant of variation by putting -8 in for y and 2 in for x and solve for k.
{{{(-8)=k/(2)^2}}}
{{{-8=k/4}}}
{{{(4)(-8)=4k/4}}}
{{{-32=k}}}
Our equation of variation is:
{{{y=-32/x^2}}}
Now we can find y when x=3:
{{{y=-32/(3)^2}}}
{{{y=-32/9}}}
Happy Calculating!!!