Linear Application Problem, STUCK HELP ASAP!

Question

Phone Charges The monthly cost C, in dollars, for calls from the United States to Germany on a certain phone plan is modeled by the function C(x) = 0.24x + 5, where x is the number of minutes used.

(a) What is the cost if you talk on the phone for x = 50 minutes?

(b) Suppose that your monthly bill is $20.36.How many minutes did you use the phone?

(c) Suppose that you budget yourself $40 per month. What is the maximum min. You can talk?

(d) interpret slope

(e) interpret the y-intercept

Answer 1

C(x) = .24x + 5

a) C(50) = .24(50) + 5

C(50) = 12 + 5 = $17

b) 20.36 = .24x + 5

15.36 = .24x

64 minutes = x

c).24x + 5 ≤ 40

.24x ≤ 35

x ≤ 145.8 minutes

d) slope = .24

e) y-int = 5