Ahistoric museum charges a rental fee plus $2 per hour for an audio tour guide. the total cost for 4 hours is $12. find and interpret the rate of change and initial value.

We can represent this problem with the following linear equation
 y = 2x + 4
 where
 y: total cost
 x: number of hours
 the slope of the line is
 m = 2
 Which means that for every hour of audio tour guide they charge $ 2.
 For "zero" hours (x = 0) a rental fee of $ 4 must be paid.