Answer: 0.09m > 56.60 + 0.07m, where m > 2830.
Explanation:
Let's assume that Plan A costs more than Plan B for monthly phone use greater than some value m, where m is the number of minutes of phone use in a month.
For Plan A, the monthly cost can be expressed as:
Cost_A = 0 + 0.09m = 0.09m
For Plan B, the monthly cost can be expressed as:
Cost_B = 56.60 + 0.07m
To find the value of m for which Plan A costs more than Plan B, we need to set the two costs equal to each other and solve for m:
0.09m = 56.60 + 0.07m
0.02m = 56.60
m = 56.60 / 0.02
m = 2830
Therefore, for monthly phone use greater than 2830 minutes, Plan A will cost more than Plan B.
In mathematical notation, we can express this as:
0.09m > 56.60 + 0.07m, where m > 2830.