Question

Please help? I left my book at school...

f(x) varies inversely with x and f(x) = –15 when x = 30. What is the inverse variation equation?

Answer 1

\(y = \frac{k}{x}\)
\(-15 = \frac{k}{30}\)
\(k = -450\)

Answer 2

\(y=\frac{k}{x}\) is the general form for your inverse variation so you just need to substitute \(k\) back.

Answer 3

I don't know what numbers go where,,, @Richard_Feynman

Answer 4

\(k\) is the constant of proportionality and \(x\) is your variable.