In 2011 online sales were $191 billion, and in 2015 they were $255 billion. (a) Find a linear function that models these data, where is the sales in billions of dollars and x is the year. Write S(x) in slope-intercept form.
(b) Interpret the slope of the graph of S.
(c) Determine when online sales were $239 billion.
(a) Write S(x) in slope-intercept form.
S(x)=0
(b) Interpret the slope of the graph of S. Choose the correct answer below.
A. Sales increased by $16 billion in next 4 years.
B. Sales decreased, on average, by $16 billion/yr.
c. Sales increased, on average, by $16 billion/yr.
D. Sales decreased by $16 billion in next 4 years.
(c) Online sales were $239 billion in the year