When we first learn arithmetic, we focus on working with whole numbers. Then, we extend our understanding to fractions and negative numbers. In algebra, we transfer these same skills to expressions involving variables. What elementary skills have you used so far in this course, and how have you extended them?

Aretha wanted to gather data about the cost of local bowling leagues in her area. she plotted the data and determined that the average bowling league costs consist of a one-time registration fee and a monthly fee modeled by the equation y = 15x + 20. identify and interpret the y-intercept in this model. the y-intercept is 20. this is the cost per month. the y-intercept is 20. this is the cost of registration. the y-intercept is 15. this is the cost of registration. the y-intercept is 15. this is the cost per month.