​On-the-Go Phone Company has two monthly plans for their customers. The EZ Pay Plan costs​ $0.15 per minute. The 40 to Go Plan costs​ $40 per month plus​ $0.05 per minute.
​a) Write an expression that represents the monthly bill for x minutes on the EZ Pay Plan.
​b) Write an expression that represents the monthly bill for x minutes on the 40 to Go Plan.
​c) Write an equation to represent the point at which the monthly bills for the two plans are equal.
​d) Solve the​ equation, showing each step.
​e) Interpret the solution of the equation within the context of the problem.