The scatter plot shows the average monthly temperature, x, and a family's monthly heating cost, y, for 23 different months.
(a) Write an approximate equation of the line of best fit for the data. It doesn't have to be the exact line of best fit.
(b) Using your equation from part (a), predict the monthly heating cost for a month with an average temperature of 25 °F.
Note that you can use the graphing tools to help you approximate the line.