Answer:
y = 2x
Step-by-step 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 = [tex]\frac{y}{x}[/tex] = [tex]\frac{0.8}{0.4}[/tex] = 2
y = 2x ← equation of variation
