Answer:
23.50=1.50x+4, m=13
Explanation:
The $4 is a constant, no matter how many times the app is used, the $4 amount will stay. The $1.50 is dependant on how many times the action is preformed so it has to be put with M. Overall, the cost is 23.50 which is why the entire equation is equal to $23.50.
Subtract 4 from the 23.50, then divide that result with 1.50