Question

Suppose that y varies inversely with x, and y=2 when x=10.

(A) write an inverse variation equation that relates x and y

(b) find y when x= 4

Answer 1

see explanation

Explanation:

Given that y varies inversely with x then the equation relating them is

y =
`(k)/(x)` ← k is the constant of variation

(A)

To find k use the given condition y = 2 when x = 10

k = yx = 2 × 10 = 20, thus

y =
`(20)/(x)` ← equation of variation

(B)

When x = 4, then

y =
`(20)/(4)` = 5