Answer:
see explanation
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 = 21 when x = 14 , then
21 = 14k ( divide both sides by 14 )
= k , that is
k =
= 1.5
y = 1.5x ← equation of variation
when x = 40 , then
y = 1.5 × 40 = 60