Answer:
The constant of proportionality k = 12
Hence, option A is true.
Step-by-step explanation:
We know that when 'y' varies directly with 'x', we get
y ∝ x
y = kx
Where 'k' is called the constant of proportionality.
In our case,
The given equation is
y = 12x
comparing with the equation y = kx, we can say
k = 12 which is the constant of proportionality.
Therefore, we conclude that:
The constant of proportionality k = 12
Hence, option A is true.