Question

assume that y varies inversely with x. If y = -4 when x = 1/2 , find x when y=2

Answer 1

it is given that x and y have inverse relation

so K = xy

put y = -4 and x = 1/2

$\begin{gathered} k=\frac{1}{2}\times-4 \\ k=-2 \end{gathered}$

now

y = 2

then'

$\begin{gathered} -2=x\times2 \\ x=\frac{-2}{2} \\ x=-1 \end{gathered}$

so the value of x = -1

$\begin{gathered} x\infty\frac{1}{y} \\ x=\frac{K}{y} \\ K=xy \end{gathered}$