Your variable is r for the number of rooms
So your equation is 395= 35*r + 80
First subtract 80 from both sides of the equation
315 = 35r
Next divide 35 from both sides of the equation
And your final answer is 9 rooms in total he sprayed.
Total cost = 35(#ofrooms) + 80
So you want me to write sentences?
I do not know for sure but im almost 100% sure that the answer is y=97 and x=1.08 i hope that is correct and that it helps you out.
What are the constraints?
When you graph the constraints the four points you can use are (0,0), (10,0), (0,2), and (6,2).
(10,0) is the point that gives you the maximum value which is 40.