Paul's plumbing charges a flat fee of $90 plus $40/h for a plumbing job. perfect pipes charges a flat fee of $60 plus $55 for a plumbing job.
a. write expressions to represent the total costs of a plumbing job for each company. let h represent the time, in hours, of a plumbing job. be sure to label the expression for each company!
b. is the cost of a 3-hour-long plumbing job the same at both companies. write and use an equation to find out. show all work!

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.