50 POINTS A cell phone company charges a monthly base fee for a phone plan with a limit of 500 text messages. A $0.10 fee is cha
rged for each message beyond the limit. An equation that models the month's total cost, y, based on the number of text messages beyond the limit, x, is shown below. The rate of change in the equation represents how much the changes based on the . The monthly base fee is .
