Please help me with this

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=

Consider the first four terms of the sequence below. what is the 8th term of this sequence?

Determine if this is a solution to the system