Hello, thank you for taking the time to post your question!
Basically you are given two points and then asked to find the linear equation between them. So we have the point (9, 4076) and the point (20, 1106) and we’re trying to get an equation in the form
y = mx + b, where “m” is the slope and “b” is the y-intercept
m = (y2 – y1) / (x2 – x1) = (1106 – 4076) / (20 – 9) = -2970 / 11 = -270
that means that on average the number of stores per year decrease by 270 stores/year
then you can plug in one of the points to find “b”
4076 = -270(9) + b
b = 6506
meaning the full equation here is
y = -270x + 6506
the next step of the question wants you to predict the numbers for 2016 and 2018, which would mean substituting in x = 26 and x = 28 into our equation and seeing what the resulting value is … when you do that here you find that the value is negative, meaning that it’s not a reasonable prediction. It wouldn’t be possible for the value to drop below 0 in this context, in other words :)
I hope that helps you get moving in a better direction on this type of question! Feel free to reach out if you have any additional questions beyond that :)
