You are right about the domain.
Answer:
b. 
f. 17 hours
Step-by-step explanation:
Charges for coming to my house = $68 (this will be the constant of the equation)
Amount charged per hour labor = $17
hours = h
Total amount paid to Mike = 357
The equation that represents this situation can be expressed as:

Solve for h
(subtraction property of equality)

(division property of equality)

Mike was in my house for 17 hours.
Let point is(x,y)
x=(2-0)/5=2/5
y=(-6-5)/5=-11/5
(2/5,-11/5)