x represents the number of minutes
y represents the total cost per month of the calling plan
Plan A
Costs $15/month plus $0.08 per minute
You can express the monthly cost as
[tex]y=15+0.08x[/tex]Plan B
Costs $35 with unlimited calling → this means that no matter if you call one time or hours, you will pay only $35 per month
You can express the monthly cost as
[tex]y=35[/tex]The correct option is C.