Ianna buys a book for $12 and a poster for $15. Posters are on sale for 20% off. Sales tax is 9%. Which expression will calculate the cost of Gianna’s purchase?
12 + 15 - 0.80 + 1.09
12 + 15(0.80)(1.09)
(12 + 15)(0.80)(1.09)
(12 + 15 ● 0.80)(1.09)

7x+8y=-18, 4x-9y=-3 solve the system of equations

Neoli is a nurse who works each day from 8: 00 am to 4: 00 pm at the blood collection centre. she takes 45 minutes for her lunch break. on average, it takes neoli 15 minutes to collect each sample and record the patient's details. on average, how many patients can neoli see each day?

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.