PLEASE HELP:
Suppose that in 2001, the average cost of a gallon of milk was $2.43. In 2007 the average price was $4.21.
Assuming the relationship is linear, find the equation of the line that models the price of milk over time since 1999.
Round to the nearest thousandth.

Question

PLEASE HELP:
Suppose that in 2001, the average cost of a gallon of milk was $2.43.  In 2007 the average price was $4.21. 
Assuming the relationship is linear, find the equation of the line that models the price of milk over time since 1999. 
Round to the nearest thousandth.

anonymous · Answer

( 2001, 2.43)    ( 2007, 4.21)
Can you find slope of these 2 points?

anonymous · Answer

First change your independent variables (Year) into years since 1999
2001 -1999 = 2
2007 - 1999 = 8
Then you use slope, and then solve for b

anonymous · Answer

@Chlorophyll Slope: 1.78/6

anonymous · Answer

&& what do I do next

anonymous · Answer

y - y' = m ( x - x' )
 Suppose you use ( 2001, 2.43)  to plug in

anonymous · Answer

& 2001 , 2.43 being x1 and y1?
or no

anonymous · Answer

Yes

anonymous · Answer

just leaving the y alone and the x, sorry i really dont know

anonymous · Answer

Yes, after distribute and simplify you got the linear line y = mx + b