y varies inversely as the square of x. So we can write the relation between x and y as:
[tex]y= \frac{k}{ x^{2} } [/tex]
where k is a constant of proportionality. It is given that y = 7/4 when x = 1.
Using these values, we can write:
[tex] \frac{7}{4}= \frac{k}{1} \\ \\
k= \frac{7}{4}[/tex]
So, now the equation in terms of x and y can be written as:
[tex]y= \frac{7}{4 x^{2} } [/tex]
We are to find y when x = 3. So we can write:
[tex]y= \frac{7}{4(9)}=\frac{7}{36} [/tex]
Thus, for x= 3 value of y will be 7/36
