The total cost of a meal at a restaurant includes the original cost of the meal, the meal tax, and the tip, which is usually a percentage of the original cost of the meal. a. Write a formula for the total cost of a meal ''C'' in terms of the original cost of the meal ''C_(0),'' the meal tax rate ''x'' written as a decimal, and the tip rate ''t'' written as a decimal.

b. Solve for the tip rate of a meal with a given total cost, original cost, and meal tax rate. Show your work.