I need help on number 5​

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 tt of tokens james has is a function of gg, the number of games he plays

What is the standard form of -5x^2+2x^4-11+x^3+3x

Write an equation for the function that includes the points (1,4/5) and (2,2/3)