Problema Solution
Suppose that the monthly cost of a long-distance phone plan (in dollars) is a linear function of the total calling time (in minutes). When graphed, the function gives a line with a slope of 0.09 .
The monthly cost for 34 minutes of calls is $18.58 . What is the monthly cost for 37 minutes of calls?
Answer provided by our tutors
x is the monthly cost for 37 minutes of calls.
(x-18.58)/(37-34)=0.09
x=18.58