Answer:
y = 9
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 = - 15 when x = 5, thus
k = [tex]\frac{y}{x}[/tex] = [tex]\frac{-15}{5}[/tex] = - 3
y = -3x ← equation of variation
When x = - 3, then
y = - 3(- 3) = 9