Assuming that this is a linear relationship you must find the rate of change...$23.81-$20.70= $3.11. 3.11 is how much it changed that year. What that also gives you is how much you bought the post for at 0 years by subtracting $20.70 and the $3.11 = the price of the poster. This gives us the equation y=3.11(x)+17.59
Where Y is the value and X is the amount of years.
She ate 10 cookies
1/3 of 30 is 10
This is in 2 point form
(y2-y1)=m(x2-x1)
(9-5)=3/5(x-3)
x=29/3
