13x+4
Combine like terms
If there is a minus sign count it as a negative
C and d is indubitably correct
Answer: The number of ceral boxes per day.
Because the slope will be [rise of the grah of the model function] / [run of the graph of the model function].
rise = [increase in the number of cereal boxes sold]
run = [days elapsed ]
rise / run = number of cereal boxes sold per day
