system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do you find the line of best fit on a scatterplot?
gpt
There are different ways to do it depending on what you care about most.  The most common way is doing a least squares regression.  Basically you use calculus to figure out the line that makes the square of the distance from that line to each point the smallest.   The math of it is a bit above an ELI5 but you can look up least squares.