The revenue from selling x shirts is r(x)=12. the cost of buying x shirts is c(x)=5x+20. the profit from selling x shirts is p(x)=r(x) - c(x). what is p(x)?

The profit function would be p(x) = 7x - 20

Step-by-step explanation:

In order to find this, start by listing just as asked.

p(x) = r(x) - c(x)

Now input the functions where indicated

p(x) = 12x - (5x + 20)

p(x) = 12x - 5x - 20

p(x) = 7x - 20

step-by-step explanation:

12: 00 p.m. to 7: 00 p.m. is a total of 7 hours.

4: 00 p.m. to 7: 00 p.m. is a total of 3 hours.

this means that from 4: 00 p.m to 7: 00 p.m. this represents 3/7 of what was lost from 12: 00 p.m. to 7: 00 p.m.

after knowing this, after doing 11,600 - 6,800 = 4,800

4,800 represents 3/7 of what was lost for 7 hours.

we then divide 4,800 by 3 which gets 1,600.

because we know that 1,600 represents 1/7 of how much water was lost, we just have to multiply by 7, which gets 11,200.   after adding 11,200 to how much water was left at 7: 00 p.m. which was 6,800. 11,200 + 6,800 = 18,000

this means that the pool originally had 18,000 gallons in the pool.

you can also check your work by doing 18,000 - 4(1600), which becomes           1800 - 6400 which gets you 11,600.