With no advertising your newspaper has a circulation of 6000 papers. For each dollar you spend on advertising, your newspaper circulation increases by 5 papers. You earn a profit (taking into account advertising expense) of 9 cents for each paper sold, but you must pay $500 to have the papers delivered. Find a formula that gives the total profit P, in dollars, that you earn if you spend a dollars on advertising.

Step-by-step explanation:

First, the profit formula:

PROFIT= TOTAL REVENUE - TOTAL COST

Next, note the points:

- Without Advertisement, Q = 6,000 where Q is quantity supplied

- A formula that gives the total profit P in dollars must take into account that 100cents = 1dollar

- Here, only a dollar is spent on advertisement, hence, Q = 6005

- Advertising expenses have been accounted for and [P = 9cents × Q] where Q is quantity sold.

- 9 cents = 0.09 dollars

TOTAL PROFIT FORMULA = 0.09Q - 500

you need a common difference between consecutive terms to be constant, like 1,2,3,4 or 2,4,6,8, or 1,3,6,9

is only a line? i think so