Question

If y varies inversely as x, find the constant of variation if y = 2 as x = -9.

Answer 1

Constant of variation (k) = -18

Explanation:

We are given that y varies inversely as x and we are to find the constant of variation (lets assume its
`k` if
`y = 2` and
`x = - 9`.

`y` ∝
`\frac { 1 } { x }`

Changing this inverse proportionality to equality to get:

`y = \frac { k } { x }`

Substituting the given values:

`2 = \frac { k } { -9 }`

`k=-9 * 2`

k = -18