Answer:
The unit rate is [tex]3\frac{\$}{ft}[/tex]
Step-by-step explanation:
Let
x ----> the number of feet
y ----> represent the cost of a piece of pipe
we have
[tex]y=3x[/tex]
Remember that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form [tex]y/x=k[/tex] or [tex]y=kx[/tex]
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
In this problem we have a proportional relationship
The unit rate is the same that the slope of the linear function or the constant of proportionality k
so
[tex]m=k=3\frac{\$}{ft}[/tex]
therefore
The unit rate is [tex]3\frac{\$}{ft}[/tex]
