Question

If y varies inversely as x. Using the coordinates (5, 3) and (x, 2.5), find the missing value x.

Answer 1

(6, 2.5 )

Explanation:

Given y varies inversely as x then the equation relating them is

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

To find k substitute the coordinate point (5, 3 ) into the equation, that is

3 =
`(k)/(5)` ( multiply both sides by 5 )

15 = k

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

Using (x, 2.5 ) with y = 2.5 , then

2.5 =
`(15)/(x)` ( multiply both sides by x )

2.5x = 15 ( divide both sides by 2.5 )

x = 6

Thus point is (6, 2.5 )