Answer:
The constant of proportionality is 4.5
Explanation:
To demonstrate the constant of proportionality, we typically use variable k. The equation can look like y/x=k or y=kx
y/x=k
9/2= 4.5
The constant of proportionality is 4.5.
To check the work, we can use the other equation, y=kx.
y=kx
y=4.5(2)
y= 9