Question

Sydney pays a flat rate of $20 plus a

rate of 7 cents per minute in her phone
plan. Which function shows the cost, "C",
of Sydney's plans as a function of time
in minutes?

Answer 1

The answer is C(t)=0.07t+20

Explanation:

20 is the starting value, or y-intercept in this case. The rate of change is 7 cents, or, 0.07. If we put this in y=mx+b format, it will come out as:

C(t)=0.07t+20