13 + k/3= 1 pls show work

Clara schumann is buying bagels for her coworkers, she buys a dozen bagels priced at $5.49 a dozen. the bakery's cost for making the bagels is $2.25 per dozen. what is the markup rate based on selling price on a dozen bagels?

Isabel graphed the following system of equations. 2x – y = 6 y = -3x + 4 she came up with the solution (2,-2). what were the 3 steps she did to get that solution? (make sure they are in the correct order)

The scatterplot represents the total fee for hours renting a bike. the line of best fit for the data is y = 6.855x + 10.215. which table shows the correct residual values for the data set?