Question

Assume that y varies inversely with x. If y = -21 when x = 4, find x when y = 7.

Answer 1

@timely

Answer 2

Know what inverse variation means?

Answer 3

no

Answer 4

\(x\) has the inverse \(\dfrac{1}{x}\). The idea is similar.

Direct variation:
\(y=kx\)

Inverse variation:
\(y=\dfrac{k}{x}\)

Answer 5

Start by solving for k. Once you know k, you can use that and the second y to find the second x.