Please help im tired :( quadratic formulas

Which recursive formula can be used to determine the total amount of money earned in any year based on the amount earned in the previous year? f(n+1)=f(n)+5

What are the excluded values? m+5/mn+3m

Ellie spent $88.79 at the computer stote. she had $44.50 left to buy a cool hat. how much money did she originally have? write and solve an equation to answer the question.