There is a sales tax of six dollars on an item that cost $93 before tax, second item cost $294.50 before tax what is the sales tax on the second item

One cell phone plan charges $20 per month plus $0.15 per minute used. a second cell phone plan charges $35 per month plus $0.10 per minute used. write and solve an equation to find the number of minutes you must talk to have the same cost for both calling plans.