I was wondering if you could answer a question I have on slope intercept form of a linear equation. I know its $y=mx+b$, but why is it $mx+b$? Don't get me wrong. I know that $m$ is the slope and $b$ is the $y$-intercept and everything, but why is it the letters "$m$" and "$b$"? I understand that they're random numbers, but why couldn't it have been "$a$" and "$b$"?
For example, in standard form, it's $ax+by+c$. They used "$a$", "$b$", and "$c$". Those are sensible numbers. (When I first the slope-intercept form, I thought "$m$" was a special number.) If you are unable to answer this, could I please be referred to a source that might be able to?
Short answer: Tradition.
Long answer: No one really knows.
You might get a lot of folk etymology though.
Other countries use other letters.
Here is an example of a bunch of people discussing it. As you see, they don't get anywhere. Link