Abowling alley charges customers a fee for every game bowled plus an initial fee for shoe rental. the total cost, y, depending on the number of games bowled, x, is shown in the table.
games cost ($)
4 13.00
7 20.50
8 23.00
10 28.00

the cost increases by $ for each game bowled.
the initial fee for a shoe rental is $
the cost increases by $ for every 6 games bowled.