Question

, if "y varies directly as x", find the constant of variation and write an equation of direct variation that

relates the two variables.
y = 0.4 when x = -1

Answer 1

k = - 0.4 , y = - 0.4x

Explanation:

given 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 = 0.4 when x = - 1 , then

0.4 = - k ( multiply both sides by - 1 )

- 0.4 = k

then constant of variation is k = - 0.4

y = - 0.4x ← equation of variation