Amy sells cupcakes. The graph shows a linear model for her sales times in minutes on different days. (a) What is the equation of the line, written in point-slope form? Show your work.
Step 1: Find the slope. m = y2 – y1 = - =
x2 – x1 -
Step 2: Use point (4,15) and slope (m) from step 1 and complete the equation in point-slope form.
y-y1 = m (x-x1) y - = (x - )
(b) Based on the model, how long did it initially take Amy to sell a cupcake? Approximately how much did
her sales time decreased each day?
Step 1: At 0 days, what was her sales time? minutes
Step 2: Amy’s sales time decreased minutes per day.
from point-slope form to slope-intercept form. Show your
work