Help m please I’m stuck on a question

How many people are we starting with? i will answer it's just i need to divide 8 by the total amount of people to get how many tables

This is what i found “an explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location). it defines the sequence as a formula in terms of n. this example is an arithmetic sequence(the same number, 5, is added to each term to get to the next term).” i hope this you for what your looking for. can you plz mark me brainliest?

Need the graph to answer this.