Question

Jessica is selling books during the summer to earn money for college. She earns a commission on each sale but has to pay for her own expenses. After a month of driving from neighborhood to neighborhood and walking door to door she figures out that her weekly earnings are approximately a linear function of the number of doors she knocks on. She writes the equation of the function like this: E(X) =7X -25, where X is the number of doors she knocks on during the week and E (X) is her earnings for the week in dollars. What does the slope of Jessica's function represent?

A. for each additional set of books she sells her earnings will increase by $25
B. for each additional door she knocks on her earnings will increase by $7
C. for each additional door she knocks on her earnings will increase by $25
D. for each additional set of books she sells her earnings will increase by $7

Answer 1

I am pretty sure the answer is D, but I'm not 100% sure

Answer 2

For each additional door she knocks on her earnings will increase by some dollars but not $25

Explanation:

Here the equation is

e(x)=7x-25

here we see that the slope of Jessica Function is 7 , hence it is the angle , the line makes with the x axis is positive and it is less than 90°

Thus we see that for every unit change in x , there is some increment in the value of e(x).