3. Tmobile charges 100 dollars for the initial phone line and then 20 dollars for every phone line afterwards.
Another phone company, ToPar, does not have any initial cost but charges 30 for each phone line.
A) Write an equation for the total cost for each company.
Equation for Tmobile:
Equation for ToPar:
B) After how many phone lines will the cost be the same.
C) When would Tmobile be a better choice
D) When would ToPar be a better choice?