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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.

Which property was used to simplify the expression? 3c+9 +4c=3c+4c+9

Taina went to the toy store and spent $21.05 on a board game, $2.75 on coloring books, and $13.22 on a model airplane. about how much money did taina spend in the toy store?