C. 1.5 hours. divide 12 by 8, and you get 1.5.
Answer:
The cost increase for each square of carpet by 12.
Step-by-step explanation:
The given function is

It is a slope intercept form of the line

Where m is the slope and b is y-intercept.
Therefore the slope of given function is 12 and the y-intercept is 50.
It means the initial ot fixed cost of the carpet is 50 and the cost increased by 12 for each square of carpet.
If she starts with $8000, she has only $7000 to go.This is reduced by $850 per month.
$7000 - $850x
Answer and workings in the attachment below.