103k views
2 votes
HELP!!...................

HELP!!...................-example-1

2 Answers

1 vote
(r-c)(5) is equivalent to r(5) - c(5). Since r(x) is the amount of money that a business earns and c(x) is the amount of money that the business uses, r(x) - c(x) is the business’s profit. We input 5 into r(x) = x^2 + 5x + 14 to get 64. We input 5 into c(x) = x^2 - 4x + 5 to get 10. We substitute 64 for r(5) and 10 for c(5) in r(5) - c(5) to get 64-10, or 54. Since the problem says that it is in hundreds of dollars, the amount of profit the business makes is $5400 after its fifth month
User Crews
by
5.6k points
2 votes
solve for r and then c by replacing x with 5 then subtract:

r = x^2 +5x + 14 = 5^2 +5(5) +14 = 25 +25 +14 = 64

c = x^2-4x +5 = 5^2-4(5) + 5 = 25-20 +5 = 10

r- c = 64-10 = 54

so the store will have a profit of 54,000 after it's 5th month

Answer is C