Answer:
![C=75t+100](https://tex.z-dn.net/?f=C%3D75t%2B100)
Step-by-step explanation:
Let
C(t) ---->the total cost of the electrician's services in dollars
t ---> the number of hours
we know that
The linear function in slope intercept form is equal to
![C=mt+b](https://tex.z-dn.net/?f=C%3Dmt%2Bb)
where
m is the slope or unit rate
b is the y-intercept or initial value
In this problem we have
the y-intercept is equal to
----> set fee
we have the ordered pair (2,250)
substitute the given values
![250=m(2)+100](https://tex.z-dn.net/?f=250%3Dm%282%29%2B100)
Solve for m
![2m=250-100](https://tex.z-dn.net/?f=2m%3D250-100)
![2m=150](https://tex.z-dn.net/?f=2m%3D150)
![m=\$75\ per\ hour](https://tex.z-dn.net/?f=m%3D%5C%2475%5C%20per%5C%20hour)
The linear function is equal to
![C=75t+100](https://tex.z-dn.net/?f=C%3D75t%2B100)