Final answer:
The rate of change for Alex's cell phone bill situation is $5 per use, representing a linear relationship between usage and cost.
Step-by-step explanation:
The rate of change in the situation described is the amount Alex's bill increases each time she uses her cell phone. Since Alex pays a fixed amount of $230 every month on her account, and an additional $5 is added to her bill each time she uses the phone, the rate of change is a constant $5 per use. This situation represents a linear relationship between the number of times the phone is used and the total bill.
The rate of change for this situation can be calculated by determining the slope of the linear equation that represents the relationship between Alex's total bill and the number of times she uses her cell phone.In this case, the equation would be y = 230 + 5x, where y represents the total bill and x represents the number of times the cell phone is used.The rate of change, or slope, is the coefficient of x in the equation, which is 5. This means that for each time Alex uses her cell phone, her bill increases by $5.