Question

Neil has been running a tutoring business since 2005. He charges a monthly fee for weekly tutoring sessions and a phone help line. Each year, he has increased his fee by the same amount. The table shows what Neil charged each customer for two given years of his business: Year Annual Tutoring Fee 2005 $1200 2008 $1350 A. What is the rate of change and initial value for Neil's business? How do you know? B. Write an equation in slope-intercept form to represent the fees that Neil charges each year.

Answer 1

Rate of change is the same as slope in this case.
(1350-1200)/(2008-2005) = 150/3 = $50 increase per year
The initial amount he started charging was $1200 a year.
y = 50x + 1200, where x represents the number of years since 2005.