Answer:
y = [tex]\frac{15}{2}[/tex]
Step-by-step explanation:
Given y varies directly with x then the equation relating them is
y = kx ← k is the constant of variation
To find k use the condition y = 10 when x = 20
k = [tex]\frac{y}{x}[/tex] = [tex]\frac{10}{20}[/tex] = [tex]\frac{1}{2}[/tex]
y = [tex]\frac{1}{2}[/tex] x ← equation of variation
When x = 15, then
y = [tex]\frac{1}{2}[/tex] × 15 = [tex]\frac{15}{2}[/tex]
