Question

If x and y vary inversely, and x = 8 when y = 1/4, what is y when x = -4?

Answer 1

`y \propto \frac 1x\\\\\implies y = \frac kx \\\\\implies \frac 14 = \frac k{8}\\\\\implies k=2\\\\\text{When}~ x =-4\\\\y = (k)/(x) = (2)/(-4)= -\frac 12`