13. If r + 9 = 42, does r + 9 – 9 = 42 +9? Why why not? I forgot to put spaces last time, and there's no negative numbers

James is playing his favorite game at the arcade. after playing the game 3 times, he has 8 tokens remaining. he initially had 20 tokens, and the game costs the same number of tokens each time. the number t of tokens james has is a function of g, the number of games he plays. write the function’s formula? t=