Question

If Y varies inversely as X^2, determine what Y would be if X = 2 and another point on the equation is (1,8).

The answer I got was y=1/2^2=1/4

I'm not sure I worked this out correctly, is this correct?

Answer 1

no.

y=k/x^2 then consider the point 1,8
8=k/1^2 k=8

y=8/x^2
if x is 2, then y=2

another way to think this out: y is 8 when x is one, so if you double x, then y must be changed by 1/4, or y=2

Answer 2

Thank you!