Question

If y varies inversely as the square of x

if y equals to 8 when x equals to 4 find x when y is 25/36 ​

Answer 1

`\qquad \qquad \textit{inverse proportional variation} \\\\ \textit{\underline{y} varies inversely with \underline{x}} ~\hspace{6em} \stackrel{\textit{constant of variation}}{y=\cfrac{\stackrel{\downarrow }{k}}{x}~\hfill } \\\\ \textit{\underline{x} varies inversely with }\underline{z^5} ~\hspace{5.5em} \stackrel{\textit{constant of variation}}{x=\cfrac{\stackrel{\downarrow }{k}}{z^5}~\hfill } \\\\[-0.35em] \rule{34em}{0.25pt}`

`\stackrel{\begin{array}{llll} \textit{`

`8=\cfrac{k}{16}\implies 128=k~\hfill \boxed{y=\cfrac{128}{x^2}} \\\\\\ when~y=(25)/(36)\textit{ what is`