A telephone company offers two plans with per-minute charges. Plan A involves a monthly rental of $12, and call charges at 7¢ pe
r minute. Plan B involves a monthly rental of $15, and call charges at 5¢ per minute. Write an inequality in terms of the number of minutes which shows when Plan A is less expensive than Plan B. Solve the inequality, showing the steps in your work.
Plan A 12+.07(x) Plan B 15+.05(x). Substitute a number in for x such as 20 then plug in 12+.07(20) and 15+.05(20) and plan A would equal 13.4 a month and Plan B would equal 16 a month.