Respuesta :
Answer:
x = - 5
Step-by-step 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 = - 18 when x = 3 , then
- 18 = 3k ( divide both sides by 3 )
- 6 = k
y = -6x ← equation of variation
When y = 30 , then
30 = - 6x ( divide both sides by - 6 )
- 5 = x
Answer:
[tex]y \: varies \: directly \: as \: x \: mean \\ \: y \: increase \: or \: decrease \: with \: x \\ y = - 18 \: \: \: \: x = 3 \\ y = 30 \: \: \: x = ? \\ - 18 ? = 90 \\ ? = - 5 = x[/tex]