Finding the equation of the line of best fit.

Hello

Basically I have a question where I have sketched two graphs for the first part. The second part of the question is telling me to find the equation of the line of best fit.

So I started with y=mx+b. From there I have to find m or the slope, which is:

slope=
y2 - y1
x2 - x1

But where do I get the two points on my graph? I have tried two random points, but I am getting weird answers for the slope.

After you get the slope you then plug in the slope and any point (X,Y) on the graph and thats how you get b or the y-intercept right?

Usually the phrase "line of best fit" refers to many data points (at least, more than 2, and usually more than 10), through which you want to fit a single line. In that case, you need to use some sort of statistical estimator, such as least squares, to compute the slope and intercept of the line. Is that your situation?