In the algebraic equation:
y=mx+b
Why does the letter “m” represent the slope?
Couldn’t “s” do just as good a job. It seems that it would be easier to remember.
Maybe it is the ‘magnitude’ of the the difference between values of y. That was a WAG, but then why is the y-intercept b? Me, I’m just glad there’s something out there that makes more sense than the ‘standard’ form.
Because ‘s’ looks like 5. A lot of people would look at the equation and think they just hadn’t solved the intercept yet. y=5x+b.
Jman
I’m not sure why the y intercept is “b”, but one way to think of it is:
“b” is the first letter of “bi”. “Bi” rhymes with “y”, as in y-intercept.
Mneumonic device.
The only thing is, I can’t make sense of where “m” was derived from, and how to assess it to this equation.
I have seen a used as the x-intercept, so b makes sense for the y-intercept. About m, I don’t know, but it could be from a foreign language, such as French, German, or Latin.
Actually, no one is really certain why “m” is used for slope.
The two most common theories I’ve seen are:
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It stands for “montrer/monter” which is French for “to climb” (I’ve seen this word spelled both ways, I don’t speak French and don’t know which is correct).
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It stands for “modulus of slope”.
Just theories, though; by no means are these definitive answers. You can find more speculation here.
What Cabbage said. I found a neat site called Earliest Use of Various Mathematical Symbols. On their geometry page they say
My advice is to not even try and figures stuff like this out. Great ignorace-fighting technique, I know, but in my last physics class, a friend and I went through every letter in the English and Greek alphabets and were able to think of something each one represented. Capital and lowercase, BTW. Many had two or three or more meanings. After a while, it’s just a matter of “which letter haven’t we used in a while?”
If you make the slope S and the y-intercept i, it becomes y = sx + i, which looks like y = 5x + 1. Probably not the only reason, but it might be one of them.
b stands for base (at least in french).
And the term Cabbage was refering to is monter (to climb). Montrer means to show.
OK I’ve got to ask, is this really the standard letter denoting the slope, and to whom? American textbooks? I don’t think I’ve ever seen this used - y=ax+b seems a more natural choice of letters to me, but s is also as good as any.
In Ireland in both school and university it was “y=mx+c”, where c stands for “constant”. Can’t help with “m” though.
I think you’re correct.
For the reason you stated, I hate it when “S” is used in any equation. The Laplace Transform comes to mind; when doing those, I always use a “$” in place of the “S”.
Same goes for model numbers on equipment.
Kinda sexy, though. Might improve the image.
I just figured “s” was used for something else. Doesn’t s have another meaning in math? (I can’t remember any equations using it). I thought they tried to use different letters so you would know which equation you were dealing with.
S represents entropy in some equations.