Question

Eliza earns $400 per week plus $15 for each new costumer she signs up. Let cool represent the number of new customers. Eliza signs up . Write an algebra expression that show how much she earns in a week.

Answer 1

Well, we know that She will earn $400 regardless how many customers he signed. Assuming that customers is x, the amount she earn per week is y, the formula would be : 
y = 400 + 15x

hope this helps