The cost, c, of a health club membership is related linearly to its length in months, m. If a 12-month membership costs $260 and an 18-month membership costs $380, which equation can be used to find the cost of a 30-month
membership?

Honor code

zwallace30 avatar

zwallace30

02/15/2017

Mathematics

High School

+5 pts

Answered

He cost, c, of a health club membership is related linearly to its length in months, m. If a 12-month membership costs $260 and an 18-month membership costs $380, which equation can be used to find the cost of a 30-month membership?

A) c - 380 = 1/20(30-18)

B) c - 18 = 20(380-30)

C) c - 380 = 20(30-18)

D) c - 18 = 20(30-12)

2

SEE ANSWERS

Answer Expert Verified

4.0/5

23

dzharvey00

Ambitious

25 answers

1.3K people helped

Treat the c formula as a line. c = sm +b; where m= number of months.

using the two examples:

260 = 12s +b

380 = 18s + b

solve for s & b:

s = 20

b =20

So a 30-month membership is:

c = 20(30) + 20 = 600

Solve C for c and you get 600

Step-by-step explanation:

step-by-step explanation:

descending order means to order the polynomials from the term with the largest exponent to the term with the smallest exponent.  

therefore, the correct answer is d.