The table below models the cost, y, of using a high-efficiency washing machine and a standard washing machine over x number of years. Which equation represents the cost of the high-efficiency washing machine over a given number of years?

Which equation represents the cost of the standard washing machine over a given number of years?

After how many years of use would the washing machines cost the same amount?

Which washing machine would be the more practical purchase if kept for 9 years?