Question

Find an equation of variation where y varies directly as x and y = 0.8 when x = 0.4

Answer 1

y = 2x

Explanation:

Given that y varies directly as x then the equation relating them is

y = kx ← k is the constant of variation

To find k use the condition y = 0.8 when x = 0.4

k =
`(y)/(x)` =
`(0.8)/(0.4)` = 2

y = 2x ← equation of variation